21.08.2014
PolyEquipements Boutique - Votre devis en quelques clics - Reception, scenique, mobilier urbain - Notre catalogue - Chaises et Assises - Chaises Pliantes - Chaise Pliante REAVERConnexion a mon compte Mot de passe oublie ? You'd need a magnifying glass to find it, but there is a tiny pinhole in the epoxy coating of this workhorse demo-model Annapolis Wherry, at the joint where the seat meets the hull. I hope this warts-and-all tour of wear and tear in the CLC demo fleet has been been helpful in visualizing how these lightly-built stitch-and-glue boats hold up over the years, and given you some ideas about preventative maintenance. This Shearwater 17 was built in 2005 and still looks almost new, in spite of hundreds of demos every year. Paint is used to decorate, protect and prolong the life of natural and synthetic materials, and acts as a barrier against environmental conditions. Paints may be broadly classified into Decorative paints, applied on site to decorate and protect buildings and other objects, and Industrial coatings which are applied in factories to finish manufactured goods such as cars.
Paints are formulated according to their proposed use - primer, undercoat, special finishes (matt, gloss, heat resistance, anti-corrosion, abrasion resistance). Figure 1  Contents of a white gloss (alkyd) paint and a white matt emulsion (acrylic) paint.
The binder in many emulsion paints is based on homopolymers or co-polymers of ethenyl ethanoate (vinyl acetate) and a propenoate (acrylic) ester. Other acrylic esters used as co-monomers with ethenyl ethanoate are ethyl propenoate, butyl propenoates, or a co-polymer of butyl propenoate and methyl 2-methylpropenoate.
The polymers used in these paints are carried in water (water-borne emulsion paints) which as described above are much better for the environment than paints in which the binders are in organic solvents. Figure 2  Water-borne emulsion paints are used as decorative paints, particularly for the inside and outside of buildings (including masonry paints and exterior primers).By kind permission of AkzoNobel. Emulsion paints are so-called as they are made by a process known as emulsion polymerization, in which the liquid monomers to be polymerized are first dispersed in water, as an emulsion. Figure 3  Graph showing relationship between relative molecular mass and viscosity for solution and dispersion polymers.
Acrylic resins may also be used in industrial paints, either as water-borne emulsion paints or as solvent-borne paints. Such a compound is known as a crosslinker for it produces, on reaction with the resin, a three-dimensional structure similar to the polyurethane formed from a polyol and an isocyanate. This reaction proceeds relatively slowly at room temperature, allowing enough time for the paint to be applied, after which the solvent thinner evaporates and the painted item is placed in an oven to accelerate the chemical reaction.
The alkyd resins, which generally have relative molecular masses in the range of 10 000 - 50 000, are usually carried in organic solvents (solvent-borne paints).
Once the alkyd resin is applied, the pendant oil drying groups react with oxygen in the air to form a cross-linked, hard thermoset coating, with a high molecular mass. The value of n can be controlled to give a range of resins varying from viscous liquids to solids with high melting points. The most common inorganic pigment is white titanium dioxide (titanium(IV) oxide) which provides over 70% of total pigments used (Unit 51). Powdered metals such as zinc and some metal compounds, for example zinc phosphate, have corrosion inhibiting properties. As the paint dries, a film is formed which adheres to the surface of the material to which it is being applied. Emulsion paints dry by a physical process involving the evaporation of water followed by coalescence of the polymer droplets and their subsequent integration into a hard polymer matrix that acts as a binder for the pigment. On applying gloss paints, the alkyd polymer cross-links by an oxidation reaction with oxygen in the air once the solvent has largely evaporated. Numerous methods are used including: brush, roller, dipping, flowcoating, spraying, hot spraying, electrostatic spraying, airless spraying, electrodeposition, powder coating, vacuum impregnation and immersion. Water-based gloss paints are now available but the initial gloss of the finish is usually not as high as organic solvent based paints. High solids paints (which are solvent-based) are now available but not without compromises in cost and performance.
Powder coatings are used in particular for goods such as bicycles and white goods (refrigerators, washing machines). Due to the considerable expense of launching space vehicles, there is push to reduce the weight of the satellites and spacecraft.
A coating which can withstand first atomic oxygen etching, then high energy electromagnetic radiation would be ideal. Since polysiloxane coating exhibited bothatomic oxygen and UV-resistance, we propose using a polysiloxane backbone for our protective coating. Once prepared, the polysiloxanes will be formulated with pre-hydrolyzed TEOS oligomers, and the zirconium sol-gel precursor zirconium tetra n-propoxide will be used in conjunction with zinc alkoxides to protect the underlying composite form UV-induce degradation. There is a concerted and focused push to develop protective space coatings for vehicles in low earth and geosyncronous orbit. A synthetic scheme was developed to prepare cationically polymerizable methyl, cyclopentyl, and cyclohexyl substituted polysiloxanes.
Buildings have an impact on people and the environment throughout their entire lifecycle, starting with extracting resources from the earth to putting them back in the earth, or burning them, at the end of their lives.
The combination of wood and the Passive House standard is a common-sense approach that can have a very positive lifecycle impact on the environment. Everything in buildings comes from natural resources, some of which grow relatively quickly above the ground (e.g. The real ‘weight’ of a material—including resources, water, and energy used at the entry point of a manufacturing facility—compared to the material that comes out at the other end is referred to as the ‘ecological backpack.’ This measures the environmental impact of manufacturing products. In many cases, the process of constructing buildings is antiquated, relying on manual and labor-intensive onsite processes. The natural resources needed to produce and deliver the energy consumed to heat and cool buildings for lighting, appliances, and water is the highest of all six lifecycle steps. Wood from buildings can be recovered for use in other buildings or be employed to create furniture or other products. In creating energy-efficient buildings, one of the most important goals is to accurately predict during the design stage how a structure will perform when occupied—not only the natural resources used to produce it, but also the ongoing energy consumed for its regular operation. There are three main ways to make a building energy-efficient—using less energy, generating more energy with renewable resources, or taking a combined approach of the two.
In winter, heat in buildings is often needlessly lost due to conditioned air escaping through cracks in the envelope. New wood building systems have been developed to offer greater airtightness to minimize energy consumption. New building materials created through advanced versions of engineered wood are changing  non-residential construction. Europe is far ahead of North  America when it comes to  monitoring and reporting energy consumption of buildings and homes. It is not enough to design buildings using energy efficiency strategies—they must also be constructed accordingly and then meet the energy consumption goals of the design during operation. The European Union (EU) requires every building have an Energy Performance Certificate listing the energy consumption of space heating and cooling, water heating, lighting, and appliances. In the United States, energy consumption in buildings is compared to the local energy code requirements in relative numbers as opposed to a consumption rate. For new-generation wood projects, walls are simply stood up and windows, siding, and trim are installed.
Preparation for blower door test for LCT ONE—aPassive House-certified,eight-story wood officebuilding in Austria. Passive House is a European-developed standard that has recently found its way to North America. The Passive House standard is a whole building strategy that harmonizes all aspects of a structure beginning with data on local weather and solar orientation and continuing with the design, layout, foundation, framing, and insulation systems to reduce, or even eliminate, thermal bridging.
Specific to thermal properties, it is important to incorporate building materials that have low thermal conductivities, and design details that minimize thermal bridging. Most importantly, Passive House has a specific requirement for airtightness, which is where the biggest connection to modern wood carpentry is made.
Lighting and all appliances (including ovens, cooktops, refrigerators, toasters, and computers), generate some heat. The heat in the outgoing stale air is transferred to the incoming fresh air inside the ventilator. To combine this strategy with the choice of materials and construction methods, use of modern engineered wood products—stable, cut accurately with computerized equipment, and assembled under a controlled environment—results in airtight buildings that are automatically energy-efficient. Prefabrication and modular wood construction is helping building designers achieve this while increasing the speed of construction and reducing project cost.
When talking about wood construction, the reference points are traditionally stick-frame, or light-frame residential construction. The post-and-beam method of wood construction was prevalent in many cities at the beginning of the last century, before the industrial revolution introduced concrete and steel. The material is then fed to a wood-cutting machine that uses the computer numerical control (CNC) data to precisely cut all the elements. Instead of asking carpenters to measure, cut, and assemble walls and floors onsite, employing labor-intensive processes, the carpenters are moved in a controlled environment, where they are given the drawings and pieces for each component to be assembled, making use of overhead cranes and forklifts to protect their bodies. The advantage of this process is it optimizes the construction, guarantees stable material, and accurately cut pieces and assembled components that fit together tightly. Combining modern wood technology and Passive House strategies helps save resources and achieves energy efficiency in buildings. Using this construction process and modern carpentry skills, the building envelope’s thermal performance and airtightness can be predicted during the design stages. Overall, the use of new modern wood technologies can have a positive effect on construction industry from job creation to reduced environmental impact. The design team, including architects and engineers, can collaborate to ensure wood-based building envelopes can meet these high-performance standards. 1 There have been dozens of certified projects in North America, and the numbers are growing fast. 3 The Passive House Institute requires the test to meet the European Standard EN 13829, Thermal performance of buildings: Determination of air permeability of buildings, fan pressurization method. 4 The limitations of these types of wood assemblies are the current building codes or special approval by a jurisdiction for alternative means of design and construction. 5 For more on wood and fire resistance, see “Design of Fire-resistive Exposed Wood Members,” by Bradford Douglas, PE, and Jason Smart, PE, which appeared in the July 2014 issue of The Construction Specifier.
7 This is a consultant that collaborates with the architect, and structural, mechanical, and electrical engineers.
8 For more, see this author’s previous article, “LCT ONE–A Case Study of an Eight-story Wood Office Building,” in the March 2014 issue of The Construction Specifier. Nabih Tahan, AIA, is an international architect, Passive House consultant, and CEO of Cree Buildings Inc.
This article explores 10 frequently asked questions about exterior shading, while providing insight into available systems and how they can be an important part of the building’s environmental control. Fixed louver systems include projecting sunshades generally installed at the head of the glazing (i.e. Brise-soleil systems only address high sun angles and, as a result, they generally will only be effective on south or near south-facing elevations.
The effectiveness of fixed horizontal or vertical louvers depends on louver size, angle, and spacing.
Vertical and horizontal adjustable louver systems can be motorized, allowing louver angles to be adjusted to give more responsive shading, particularly if they are connected to an automated control system.
The method of control can range from switch operation, where occupants operate the system according to their needs, to a fully automated system that responds to the sun conditions and adjusts the louver angle to prevent any direct sun penetration. This brise-soleil system was installed at the Southern Alberta Institute of Technology (SAIT)in Calgary, Alberta. In broad terms, an exterior system is better than an interior one because it prevents a large part of the sun’s energy from reaching the glazing and entering the building. The reflected solar energy is not an issue—it remains short-wave and does not cause any heat gain. An exterior system is similar to an interior one with regards to the transmittance, absorption, and reflection of solar energy. The message is therefore straightforward—for the most effective solar control, the shading system should, wherever possible, be installed on the exterior. Some buildings, however, need to be cooled in the summer, while also have heating requirements in the winter. A well-designed shading system also contributes to comfortable working conditions which can lead to increased productivity.
It is always easier to apply exterior shading systems to a new building, as integration issues can be reviewed and connection details developed during the design phase. If an operable system is going to be used with an existing building, it will be necessary to look at the electrical requirements and determine how conduit and electrical cabling can penetrate through the facade to allow connections to be made to the blinds or shades. With both new and existing buildings, installation of an exterior shading system might involve attaching directly to the curtain wall mullions, to brick or concrete masonry units (CMUs), or through cladding to steel structure. Exterior roller shades and venetian blinds are generally installed just above or at the top of the glazing. Since exterior louver and brise-soleil systems remain fixed in place in all weather conditions, they apply more significant loads to the facade. Other issues that need to be considered include separation of dissimilar metals, cold bridging, and water penetration, as well as relative expansion and contraction between the shading system and the facade. As seen in Figure 1, the movement of the sun during the year (shown by the blue lines) is significantly different between two extremes in the United States—Miami, Florida, and Anchorage, Alaska.
The solar radiation on the east and west elevations is similar, with the maximum values occurring in the summer.
Given the variations by facade, fixed systems might work on the south elevation, but operable ones will be better east and west.


As previously highlighted, fixed louver systems are designed to take account of the maximum applied loads. Retractable systems such as exterior roller shades and venetian blinds are more lightweight than fixed systems and are designed to retract when the wind speeds are high. Ice is also a potential issue, but should not be a problem if the systems are protected in the raised position. There are numerous areas where the use of exterior shading system can help achieve credits for Leadership in Energy and Environmental Design (LEED) certification.
To justify using exterior shading systems, it needs to be demonstrated it makes economic sense to do so. In the past, it has often been the case the shading system’s performance was not taken into account when sizing the HVAC system. The traditional approach to windows has been to use interior shading systems to control light and glare, and to address solar heat gain through the HVAC system. Exterior shading systems will not be appropriate for all buildings; where they are used, however, they can make a significant contribution to the building’s performance as well as the building aesthetic.
This entry was posted in 08 00 00 Openings, 08 50 00 Windows, B20?Exterior Vertical Enclosures, B2020?Exterior Windows, Features, MasterFormat, Must Reads, UniFormat and tagged Brise-soleil systems, Exterior shading, Louver systems, Solar energy on October 1, 2014 by nonexist_molly. It is true parking decks must be protected from the harmful effects of moisture and chlorides, but there is a growing misconception installing a traffic-bearing membrane is a one-way ticket to the garage equivalent of immortality. In order to withstand the punishing abrasion which a parking deck must endure, the traffic-bearing membrane must be hard and durable.
Identifying product properties and applying appropriate selection criteria can guide the specifier in developing a customized system that will provide immediate protection, while also considering future treatment options. This test core shows epoxy penetration to thebottom of a crack, as indicated by the arrowson the concrete.
Sources of deterioration Since the interior and exterior of parking structures are exposed to the elements, they are more susceptible than other types of buildings to deterioration due to moisture, temperature cycles, and contaminants. In northern climates, parking decks are subjected to extreme corrosive and deteriorating environments. After investigating various coating systems for renovating the potable water tank at Pennsylvania’s State Police Academy, project engineers chose Tnemec’s fluorourethane exterior finish, which is specially formulated to “lock in” high gloss and color.
Le plateau est traite contre les rayons UV pour empecher la decoloration et la degradation.
Resistant aux taches et aux intemperies, tres facile a nettoyer, il est realise en polyethylene moule hautedensite (HDPE) en une seule piece et sans joint.
PolyEquipements Boutique - Votre devis en quelques clics - Reception, scenique, mobilier urbain - Notre catalogue - Tables Pliantes ou Fixes - Mange Debout - Mange Debout Bistro Pliant 74x74cm.Connexion a mon compte Mot de passe oublie ? Il pourra alors intervenir sur votre devis.Delai de livraison selon les produits et variantes de 1 a 4 semaines. Our display model Expedition Wherry is rolled outside every time we open the showroom, and lives outdoors most daylight hours, rain or shine. The binder may be dissolved as a solution or carried as a dispersion of microscopically small particles in a liquid.
This reaction is accelerated using salts of transition metals (for example, cobalt and manganese naphthenates). The requirements for an automotive topcoat, for example, will be very different to those for a decorative ceiling paint. A means of achieving this goal is to utilize lightweight high strength composites to replace load-bearing metallic exterior and infrastructure.
In addition to methyl substituted siloxane polymers, both cyclopentyl and cyclohexyl groups will be prepared.
The Soucek group has previously found that TEOS oligomers are amenable to photo-initiated cationic polymerization of cycloaliphatic epoxides, and we have proposed that in addition to condensation reactions the silanol group can also react with the cycloaliphatic epoxide.
For protective space coatings, it is proposed to use a photo-curable polysiloxane continuous phase with silicon-oxo clusters with zinc and zirconium-oxo clusters derived from sol-gel precursors.
The space environment is not suitable for organic materials due to atomic oxygen, high energy particles, and deep UV-light being able to degrade polymeric organic resins. Initially, the desired cycloalkene and dichlorosilane were reacted at high pressure (approx. To evaluate the effect of buildings in this regard, everything from the energy they consume, the waste they generate, and the carbon dioxide (CO?) they emit must be considered throughout the six major cycles below. Common sense suggests it requires less resources and energy to manufacture wood products compared to concrete and steel. Other fields, such as manufacturing automobiles, have advanced considerably using automation and an industrialized system approach to designing and building, where the energy efficiency, in miles per gallon, can be guaranteed and the assembly occurs in a modern factory. While more efficient lighting and appliances can be specified, the only way to reduce long-term heating and cooling loads is to improve the building envelope. Using a system approach to construction, buildings can be designed so they can be disassembled and separated for recycling. Even at the end of their second or third ‘life,’ wood products can be burned to generate energy or decompose naturally in the earth.
New opportunities combining modern carpentry techniques and the Passive House standard help achieve these goals.
The building industry should focus on combining the two aspects of using renewable building materials and energy efficiency to achieve comfortable buildings, while optimizing indoor air quality (IAQ) and reversing the negative effect of climate change. This is similar to a car manufacturer designing and producing a vehicle with a specific fuel economy, and then having the car actually meet that target. The certificate must be available to buyers and tenants when a building is constructed, sold, or leased. Buildings are described as being a certain percentage better than the prevailing code, rather than having their actual consumption cited.
By nature, wood is ideal for this, made up of thousands of open cells that make it difficult to conduct heat. Airtightness is measured with a blower door test.3 Air is either pumped into or sucked out of a building to see how much air is leaked, in both pressurized and depressurized states. Instead of allowing this heat to escape through a leaky building envelope, it is trapped inside a tight building envelope. This recycling (or ‘U-turn’) of ‘free’ heat’ that comes out of everyday appliances and lighting can dramatically reduce a building’s energy consumption. Modern wood construction falls under the category of heavy timber, using large-dimensioned posts and beams.
Now, wood products are beginning to increase again in popularity due to awareness over some of the negative environmental effect of products extracted and manufactured with intensive use of fossil fuels. The carpentry company receives the computer-aided design (CAD) drawings from the architect. Unnecessary framing members are eliminated and replaced with insulation to optimize energy performance.
Specifically designed tapes and gaskets are used at the intersection of panels to prevent air leakage.
To prove the performance, the envelope is tested for airtightness with a blower door test after assembly.
Obviously, it is not a one-for-one switch between wood and concrete—the architect and engineers have to run calculations for both materials to ensure the design meets the structural, seismic, acoustic, and thermal requirements. During the design stages, the passive house consultant begins the energy modeling in the Passive House Planning Package (PHPP) tool to determine the heating, cooling, and electrical loads.
For more than 30 years, he has honed his knowledge in architecture, energy efficiency, and sustainable timber-based construction methods through work in Austria, Ireland, and the United States. These systems normally only shade higher sun angles in order to allow views to the exterior, and are most effective on south-facing elevations.
The systems do not retract—they will always remain in front of the glazing—but can be moved between the fully open and closed positions.
The systems are generally controlled independently of the interior lighting systems; ideally, levels are automatically adjusted to supplement natural daylight where required.
Anything absorbed by the shading system, however, is radiated as heat on the building’s exterior. There will be some situations where this is not practical—for example, high-rise buildings with 25 floors or more. As discussed earlier in this article, exterior shading blocks a large part of the solar gain before it comes through the glazing and into the building. If a retractable exterior shading system is used, it can be turned off in the winter months, allowing the solar gain into the building and providing an element of free heating.
Exterior shade systems can help optimize the use of diffuse daylight to illuminate interiors, reducing the need for artificial lighting. Shown  above is the impact of orientation on incident solar radiation for a building in Indianapolis, Indiana.
Fixed exterior louver systems can exert significant loads on the facade, and if they are being attached to the curtain wall, mullions might need to be reinforced to support them. While the original building design would not have anticipated exterior shading, structural elements can be incorporated as required, to allow installation onto the existing facade. What are the common methods of attachment to the building facade (and what issues need to be considered)?
It is probable different brackets will be required for each situation, and these will often be developed to meet the specific project requirements. They are relatively lightweight and, because they are retracted when the wind speed exceeds a defined level, they do not apply significant loads to the facade. The brackets for the system will therefore be designed in accordance with the loads defined in local building codes, and bolts or other fasteners will also be selected based on the maximum loads. Given these issues, it is strongly recommended the shading requirements are reviewed and discussed during the early stages of the design process. Will the building’s location and the glazing’s orientation influence the choice of exterior shading system?
In Miami, fixed projections will be effective; while in Anchorage, retractable and adjustable systems offer much more flexibility in controlling solar gain.
The graph in Figure 2 shows the incidental solar radiation on different orientations of glazing for a building in Indianapolis, Indiana.
Interestingly, the maximum solar radiation on the south elevation occurs during the colder months. Although vertical louvers might work on the east and west elevations, horizontal ones are generally better for controlling the solar gain and allowing views to the exterior.
With brise-soleil systems, the loads at the attachment points might be significant, particularly if projections are substantial. Fixed louver systems need to be cleaned periodically to maintain the warranty on the paint finish, but no other maintenance work is required. Nevertheless, it is recommended they be inspected on a periodic basis to check the systems are correctly operating, guide cables (where used) are adequately tensioned, and there is no evidence of damage or general wear and tear to components. Determining the cost of an exterior shading system is a straightforward exercise, but measuring the benefits can be more difficult. In this case, it is difficult to justify the use of exterior shading since the potential cost savings from reducing the size of the HVAC system will not be achieved. Increasing energy costs, requirements for improved facade performance, and greater environmental awareness are leading architects to look for alternative solutions. There is no question more architects are considering exterior shading, and, as understanding grows, exterior shading systems will become an important element in the design of high-performance buildings. While a traffic-bearing membrane may be the best option for many situations, it is a big-ticket item, and thorough consideration is necessary to determine whether this costly investment is suited to the garage’s needs. At the same time, the membrane must be soft and flexible to bridge over moving cracks and joints without failure.
Even the best designed and constructed garages need help to survive this onslaught of corrosive forces. Moisture can facilitate reactions between certain aggregates and alkali hydroxides in the concrete, creating a cycle of expansion, cracking, and further moisture intrusion. Moisture, laden with chlorides from de-icing chemicals, tracks into garages and ultimately soaks into the concrete surface. Coupled with cold weather, water can damage concrete decks as it expands and contracts during freeze-thaw cycles. The transition metal ion (with variable oxidation state) catalyses cross linking of the polymer chains, producing a hard surface film to the paint. This also applies to chromates which, although they perform well and in the past have been extensively used on motor vehicles, are very toxic.Because volatile hydrocarbons can lead to pollution in the troposphere, coatings with lower organic solvent content are required. As a coating, ceramics are usually porous, and relatively dense with respect to the thickness needed to protect the substrate. Since phenyl groups cannot be utilized on account of light absorption, cycloaliphatic groups will be used to investigate the effects of glass transition temperature on coating performance.
The Soucek group has also previously reported that zinc acetate intercalates into zirconium-oxo-clusters formed from zirconium tetra n-propoxide during the ceramer coating curing process.
The nanophase silicon-oxo clusters will provide mechanical stiffness, and the nanophase zinc and zirconium-oxo clusters will provide additional protection and filtering from high-energy radiation and charge distribution. 250 psi) and high temperature (120° C) to yield the desired cycloaliphatic dichlorosilane. Heavy timber and mass timber products can meet the same structural and fire requirements that also govern concrete and steel. Modern wood prefabrication processes can offer new opportunities and better working conditions. Airtightness is the most important element that has made the Passive House standard succeed. Design optimization, use of recovered wood, and specifying jobsite waste to be separated and taken to a local recovery center are all ways to reduce, reuse, and recycle.


However, it is first important to eliminate heat losses due to design strategies and construction techniques.
Eliminating air leakage and heat loss in buildings by making them airtight is the most important factor for making buildings energy-efficient.
Everyone is familiar with comparing cars in terms of ‘miles per gallon,’ and now a similar unit of measurement for buildings is needed.
As new energy code updates take effect, a similar unit of measurement comparable to the Energy Performance Certificate will be established.
The standard has become successful because it has proven it can accurately predict, during the design stages, the building’s eventual energy consumption. A mechanical ventilator, with a heat recovery component, brings in fresh air into the living spaces and removes the same amount of stale air from kitchens and bathrooms.
Department of Environment (DOE) has a goal of all new commercial buildings being ‘net zero’ by 2025. Of course, this is not to say one product type is always better than another—each material has special properties and they should be combined to make hybrid buildings. Therefore, the fire regulations allow the size of structural members to be increased by 38 mm per hour for each exposed member. The individual pieces are assembled together in a facility, working on tables and prefabricated into wall, floor, and roof elements.
As proof of performance, the building can be tested for airtightness by a third party by administering a blower door test to meet the ?
Similarly, the energy performance of a building can be predicted using the Passive House standard during the design stages—through the thousands of certified buildings in Europe, the actual energy consumption during occupancy has been shown to match the predicted values.
The PH consultant then submits the calculation to either PHI or PHIUS for pre-certification.
Currently, Tahan is guiding Cree Buildings to establish a systems approach to design and construction, combining wood and energy efficiency strategies to build single-family and multi-family residential projects, along with office buildings. However, many architects and building owners still have limited knowledge about these systems and why they should be considered part of the building design. These systems are designed to remain in place at all times and need to be able to withstand all weather, including wind, ice, and snow. During the winter months, the low sun angles mean these systems provide little or no shading. They can be installed on east and west elevations, but will normally not protect occupants from the low sun in the early morning or late afternoon.
Since the systems only operate from time-to-time, and only for a few seconds to adjust the louver angle, energy usage is not significant, particularly compared with the savings that can be achieved through a reduction in HVAC requirements.
The energy absorbed by the shading system is then radiated as heat and most of this heat is then trapped inside the building, particularly if low-emissivity (low-e) glazing is used.
Since glass is not transparent to long-wave energy, little of this radiated heat gets inside the building.
In these cases, the use of a shading system inside a ventilated double facade is a potential approach, although shading is just one of many influencing factors when pursuing this type of facade construction.
During those months, glare and light control issues would be addressed with an interior shading system such as a roller shade.
More than 30 percent of the energy costs of an office building relate to artificial lighting, so if lighting needs can be reduced, significant savings can result. Finally, using exterior shading systems can significantly contribute to a building’s appearance; it can become a design feature as well as one bolstering efficient building performance.
Even with lighter, retractable systems, such as venetian blinds, it is helpful to be able to discuss attachments with the curtain wall contractor during the design phase so brackets can be specified to avoid problems such as cold bridging.
This means lighter aluminum brackets can normally be used to connect the head box to the facade.
If the systems are being connected to the curtain wall, it is possible the mullions will need to be reinforced with steel. In Anchorage, the sun has a peak altitude angle of approximately 51 degrees, which is not much greater than the highest winter sun angle in Miami of 41 degrees.
As expected, the solar radiation on the north elevation is the lowest as there is no direct sun.
If this is the case, diagonal brace rods might be incorporated into the design to allow the load to be shared between two attachment points. There is, however, a generic version known as a ‘zip system,’ which allows the fabric to be locked into side tracks. Temperature and humidity sensors can also be used to stop the blinds or shades from being operated when there is a risk of icing.
It is therefore important the shading system be considered in the context of the building as a whole, rather than as an isolated system, as it can impact several areas of building performance—notably lighting and the HVAC system. However, the mechanical consultants who deal with the heating and ventilation systems are now much more aware of the impact of effective shading, and are generally able to take this into account in their calculations. The dissolved chlorides then migrate to embedded steel reinforcement through the pores in the concrete or penetrate through cracks. Air entrainment, the deliberate incorporation of microscopic air voids in concrete, releases the internal pressure created by freezing water by permitting moisture to flow from void to void. 2 Near-White Blast, followed by a spray-applied prime coat of Series 91-H2O Hydro-Zinc, a two-component, moisture-cured, zinc-rich urethane. Each batch of ingredients is thoroughly mixed in large, stirred containers with the required additives (Figure 1).
The name alkyd is derived from alcohol and anhydride.The first step in making the alkyd polymer is the reaction between the triol and the drying oil to produce a monoglyceride.
As demonstrated by LDEF, 1 atomic oxygen etches organic media, in low earth orbit and in geosynchronous orbit high energy UV-light, protons, and electrons bombard the spacecraft.
A vapor deposited, metallic coating also can be effective against atomic oxygen and high-energy electromagnetic radiation. The siloxane pre-polymers will be functionalized with cyclohexyl epoxide and alkoxyl silane groups.
5 The proposed photopolymerization process has three reactive groups: 1) epoxide, 2) alkoxyl silane, 3) pre-hydroylized TEOS oligomers. A ceramer approach for the composite resin will result in new nanophase reinforced composite matrices. The significant features of this coating are its ability to self-heal, deflect high-energy particles, protect against deep UV-light, and be optically transparent. At some point, this metric for energy consumption of a building or apartment might even be included in the Multiple Listing Service (MLS). In the meantime, the Passive House standard is a good tool to measure and compare how much energy buildings are consuming.
Air is pumped into the tube and placed in water and the leaks are found by following the bubbles.
A net-zero energy building is hooked up to the grid and draws electricity and natural gas from the grid. Several long pieces are laminated together to make large glued-laminated (glulam) post and beams. If a member requires two-hour fire protection, 76 mm (3 in.) are added to the size required structurally. These components can be quickly erected onsite in an airtight manner, ensuring energy-efficient construction. The MEP engineers use these calculations to design the system, and the architect and structural engineers design the details to eliminate or reduce thermal bridging.
The shading performance varies depending on the system’s projection and the louver profile selected, as well as the angle of the louvers and the spacing between them. Accordingly, an exterior system eliminates one of the two sources of heat gain, resulting in much greater reduction in solar gain inside the building. The ‘g’ value is the sum of the direct and secondary solar transmittance into the building. This results in a saving in the initial capital cost—which can wholly or partly offset the shading system’s cost—as well as the ongoing running costs. Pre-tensioned side guide wires are also generally used to prevent movement of the shading system under wind load (the other option is extruded side guides) and each of these will be tensioned to approximately 22.7 kgf (50 lbf). This is particularly the case with brise-soleil systems, which project some distance from the facade and, as a result, generate significant turning moments and shear forces at the connection points.
The sun also sets much further to the south in Anchorage during the winter compared to Miami. However, the background radiation is still reasonably significant, particularly in the summer.
In locations with a cold winter climate, buildings generally require heating in the winter months.
Since hard membranes are generally inflexible, and more pliable membranes do not hold up well to abrasion, choosing the right membrane is a balancing act.
Other minerals, notably sulfates, migrate via penetrating moisture and can lead to formation of gypsum, which can lead to softening and loss of concrete strength, and ettringite, a crystalline mineral the formation of which can result in an increase in solid volume, creating expansive forces that cause cracking and a loss of cohesion and strength in the concrete. Once they reach the steel, the salts cause expansive corrosion, ultimately resulting in unsightly, destructive, and costly deterioration. Although this solution to freeze-thaw degradation has been known for years, garages may inadvertently be constructed with insufficient air entrainment, leading to premature concrete breakdown as freezing water destroys it from the inside out. This Annapolis Wherry was built for us by a subcontractor, and they are the smallest structural epoxy fillets I've ever seen in a boat that depends on them.
As previously reported, the protection mechanism involves formation of a silicon oxide layer on the surface of the coating, which inhibits further erosion of the underlying coating. Photo differential scanning calorimetry will also be used to investigate the effects of temperature, UV light intensity, sol-gel precursor concentration, and exposure time have on the rate of polymerization. In this context, it means a more sustainable production, compared to making concrete or steel, where digging for oil, coal, or natural gas and then burning it is a prerequisite to extracting the raw materials from the earth.
For buildings, smoke or other instruments are used to find leaks during a blower door test. The building also has a source for generating renewable energy such as solar or wind energy.
This lumber is stable and will not shrink or twist because it is dry, which is a great advantage for airtightness, performing much better than traditional stick frame wood with higher moisture content. The wood industry is in the process of testing new wood products such as CLT for fire and seismic performance. These items need to be evaluated during the design process to ensure the system provides sufficient shading during periods when solar gain is an issue. The secondary transmittance comprises the amount of solar radiation absorbed by the combination of glazing and shading system which is then convected or radiated into the building. The most effective shading systems, such as exterior venetian blinds, can block more than 90 percent of solar gain, having notable impact on reducing the HVAC requirements. With these types of systems, structural calculations will always be undertaken to determine the applied loads and the impact on the facade design and building connections. It may be appropriate to leave the exterior shading systems in the retracted position during these periods and allow the solar gain into the building as a free source of heating. Additionally, there are locations where no membrane performs well, such as those areas requiring a flexible membrane, yet are subject to snow plows. The lower proportion of solvent tends to slow down the drying and film hardening process, so changes are made to the structure of the polymer - increased branching tends to reduce viscosity for the same molecular mass.
When particulate matter impacts upon the satellite or spacecraft, any damage bares the organic substrate leading to rapid erosion or degradation.
Fourier transform infrared spectroscopy and H 1 NMR was used to characterize the synthesis of the polysiloxanes. The polysiloxanes were then functionalized with a cycloaliphatic epoxy and alkoxy silane groups via hydrosilation.
If the test is performed before the building envelope is covered up, the leaks can be sealed to make the building airtight.
During a one-year period, the amount of energy a building draws from the grid has to equal the energy it generates from renewable resources. The rate of polymerization was found to increase as temperature, intensity, sol-gel precursor concentration, and exposure time were increased.
Monomers, oligomers, and polymers were characterized by 1H and 29Si NMR, FT-IR, and electrospray ionization mass spectroscopy. The easiest way to meet the net-zero energy standard is to consume less energy, which is where the strategy of Passive House, in combination with modern carpentry, becomes valuable. Next, an intermediate coat of Series 73 Endura-Shield, an aliphatic acrylic polyurethane, was brush- and roller-applied.
The cycloaliphatic substitution on the siloxane backbone was chosen for raising the glass transition of the polysiloxane coating while not contributing UV-absorption, and ultimately yellowing. The photo-induced curing kinetics and activation energies were investigated using photo-differential scanning calorimetry. The coating resin (binder) is designed to have minimal UV-absorption, and zinc and zirconium-oxo-clusters are integrated into the coating to block unwanted high energy light or disperse electrical charge. Differential scanning calorimetry was used in order to observe any physical changes in the films that are brought about due to the variation of the pendant groups. The cycloaliphatic substituents raised the glass transition temperature and affected the curing kinetics when compared to a methyl substituted polysiloxane. Scratches in the finish like this are absolutely normal, though perhaps this Matunuck surf kayak has more than its fair share.



Tail light repair epoxy injection
Fix glasses frame
Light therapy cured my anxiety naturally

Comments Uv degradation epoxy resin uses

  1. 027
    Assistant used was interestingly a lot like sculptered nail gel lamp and use.
  2. Diams
    Lot of super glue on your skin arrange payment prior to returning with.
  3. Q_R_O_M
    Your bid, you'll be contractually committing to buy.