building envelopes

Building Envelopes 101

This guide will be covering innovative materials, envelope systems, ventilation, cooling, heating, lighting, human factors, and alternative energy sources.

Building practices including materials and methods have made great advances in the last century. Everything from the technology used to manufacture and create the materials to the technology now included in a home such as air conditioning and modern heating systems are examples of how home and commercial building has advanced in a short period of time.

Builders, architects, and home design professionals such as architects are including a lot of these modern materials in house designs which are available to the public with inclusions such as air conditioning, heating, and lighting systems. Also, tradesmen such as Plumbers, Electricians, and even painters, tilers and carpenters have seen advances in the materials that they use. The materials used such s pipework by the plumbers is integrated into specific ways into the building envelope system. For example, copper pipework is placed within a timber frame that is the interior wall frame in a brick veneer home. A brick veneer home is an internal timber frame that has plaster on the inside and on the exterior is a single skin of brickwork. This is a common method of home building in countries around the world.

Building envelope systems differ from country to country. This is partly because of the difference in temperature in the country and also local building materials and methods. Building envelopes also differ in the same country. In Australia in the state of Western Australia, double brick is a very common building envelope system used by Builders Perth and Builders Melbourne, were as Sydney builders are not used to using double brick as a building envelope. This is because bricks are easier and cheaper to produce in Western Australia than in other areas of the country. Also, brick companies have been very proactive in the promotion of brick as a building material. In the eastern states of Australia, single-skin brick veneer is the building envelope system of choice.

Human factors that influence building envelopes system choice and development include things such as Real estate agents and the dynamics of selling a house, Property investment, property management, Builder brokering, aesthetics, production and proximity to production sources, and affordability. Building Brokers such as building brokers Perth help people through the building process including the selection of building envelope systems that are with in the client’s budget and the builders can do a good job on building.

Unfortunately, a person’s capacity to afford different building types and systems are real. Different systems such as core-filled besser block walls are more expensive to build and are not within everyone’s reach. Mortgage brokers and banks have an influence on building envelope systems. These will also be covered in this website.

Envelope Systems

what is a building envelope

Building Envelope Systems play an important part in the building of a home. Envelope systems include brick veneer, double brick construction, ICF – insulated concrete form, Timber, tin sheeting such as Colour Bond. Builders use an envelope system that is commonly in use in the area they are in, is cost-effective, and complies with local council and building regulations.

Brick veneer is a single skin of brickwork that surrounds a building. Only a single layer of brick is used instead of 2 layers of brick which is common in some areas still. The single layer of brickwork is attached to a timber frame via metal or even plastic ties. These ties secure the outer layer of brickwork to a timber frame which is anchored to the concrete floor.

This is a cost-effective method of building in Australia. In older areas double brick construction is common, they still build in Double brick. This makes it harder for local tradesman to put their wiring and pipe work into the building envelope. With double brick they need to cut out channels for their pipework and wiring, then the pipework and wiring needs to be protected from the corrosive cement render that is used to secure the pipework and wiring in place.

Tradesmen are used to working n single brick construction. They prefer single brick because they can run their materials in the internal timer frame. This is a lot easier to work with that brick. All they need to do is drill large enough holes in the timber to run their materials thru and then secure them with something like silicone. The more difficulty a tradesman has using a material the more they will charge.

Other building envelopes are also used in different areas but now you can understand that if the local tradesman find them more difficult to use they will not be used as heavily.

Building Envelope Materials

Building envelope materials include brick, glass, concrete, timber, ICF – Insulated concrete form etc…

Each material has advantages and disadvantages when it comes to a building including its insulation properties, construction time and ease, strength, and cost-effectiveness. Common building envelope materials include bricks and timber for the home. Nowadays materials such as cladding made from aluminum, PVC, or composite materials are also available.

Timber is a natural resource that is readily available and easy to work with. The timber used for exterior cladding needs to be able to withstand the climate and it needs to weather well, be insect resistant and easy to work with

Single Skin Envelope Systems

Single-skin envelope systems are generally not as effective in insulation as double-skin systems. One advantage of a single skin system is that the single skin system can offer rapid coverage and swift completion of a weatherproof building envelope to give a high-performance building. A lot of the buildings constructed in the past were single-skin. For example, Stone and mud huts, shelters made for reading and fibrous plant material used in warmer climates. Glass and metal sheeting are 2 modern examples of single skin systems.

Tin and corrugated metal ( Steel ) sheeting.

Single Skin panels are manufactured by companies such as A Steadman & Son and consist of coated steel sheets that are rolled to form different profiles.
These panels provide a swift and effective weatherproof building envelope for the Custom FITT Steel Buildings portal frame. Examples of this include tin and corrugated metal sheeting and they are available from many manufacturers.

Stone has also been used in single and double skin systems and is a building material that has been in use for 10’s of thousands of years.

Stone is different than most structural materials in that it is not manufactured to any quality standards and little can be done to alter its basic properties. These properties can be measured by appropriate testing in order to quantify them for design purposes.
Stone is brittle rather than ductile. It is a product of nature with a wide variation in properties. When exposed to the environment it exhibits a reduction in strength. Due to its formation, it has different strengths in different directions. The strength of the stone is affected by surface finishes and humidity.

Glass

Glass is used in many commercial buildings such as office blocks and is used as the major building envelope system. It is now advantageous to have the glass costed in Chrome. This gives good savings on energy usage as the insulation properties of the glass have been improved.

Electrochromic glazings promise to be the next major advance in energy-efficient window technology, helping to transform windows and skylights from an energy liability to an energy source for the nation-building stock.

Test Results Overview


The test consisted of two side-by-side, 3.7×4.6- m, office-like rooms. In each room, five 62 x 173 cm lower electrochromic windows and five 62×43-cm upper electrochromic windows formed a large window wall. The window-to-exterior-wall ratio (WWR) was 0.40. The southeast-facing electrochromic windows had an overall visible transmittance (Tv ) range of Tv =0.11-0.38 and were integrated with a dimmable electric lighting system to provide constant work plane illuminance and to control the direct sun. Daily lighting use from the automated electrochromic window system decreased by 6 to 24% compared to energy use with static, low-transmission (Tv =0.11), unshaded windows in overcast to clear sky winter conditions in Oakland, California. Daily lighting energy use increased as much as 13% compared to lighting energy use with static windows that had Tv =0.38.

Even when lighting energy savings were not obtainable, the visual environment produced by the electrochromic windows, indicated by the well-controlled window and room luminance levels, was significantly improved for computer-type tasks throughout the day compared to the visual environment with unshaded 38%-glazing. Cooling loads were not measured, but previous building energy simulations indicate that additional savings could be achieved. To ensure visual and thermal comfort, electrochromic requires occasional use of interior or exterior shading systems when direct sun is present.