Exterior Design includes
  • Exterior sheathing: materials and construction techniques
  • Accessibility: balconies, stairs, ladders, dumbwaiters
  • Exterior lighting
  • Vegetation and garden elements
  • awnings/shade elements
  • Security (Lock)princeton_1-12_stage_6.png

Exterior Sheathing

assignment: research these three materials ,cost,structural,environmental etc analysis.

Ethylene Propylene Diene Monomer is a synthetic rubber most commonly used in single-ply roofing because it is readily available and relatively simple to apply. EPDM as a roofing membrane has advanced significantly over recent years. Problems previously associated with it included moisture gain under the membrane by vapour drive (occurring on roofs with air conditioned space beneath), and that EPDM did not like to adhere to itself and seam problems occurred. Simply adding a vapour barrier will help to resolve vapour drive.
Seaming has become simple with the addition of Factory Applied Tape, resulting in a faster installation. The addition of these tapes has reduced labour by as much as 75%. Rolls of EPDM are available with Factory Applied Tape pre-applied to one edge. This is an uncured EPDM tape. The other edge is marked to indicate the appropriate ovelap. The Factory Applied Tape is laid into the primed overlap and rolled with a little pressure. The resulting seam is stronger, and neater. Any details are taken care of with the appropriate tape. The process involves applying primer with a brush or scrubber, allowing it to flash off to touch dry (this takes moments), then applying the tape and rolling to ensure it is properly bonded.
It is a low cost membrane, but when properly applied in appropriate places, its current warranted life-span has reached 30 years and its expected life-span has reached 50 years and this continues to rise with every year that passes.
Typically, there are three installation methods. Ballasted at 1,000 lbs/sq or 10 lbs/sq.ft. with large round stones. Mechanically attached is another method and is suitable in some applications where wind velocities are not usually high. Fully adhered is the most expensive installation method but proves to give the longest performance of the three methods.
The new generation of EPDM, with a FleeceBack, has been combined with a polyester fleece backing and fabricated with a patented hot melt adhesive technology which provides consistent bond strength between the fleece backing and the membrane. This has resulted in largely eliminating shrinkage of the product, whilst still allowing it to stretch up to 300% and move with the building through the seasons. The fleece improves puncture and tear resistance considerably and .045 mil EPDM with a fleece backing is 180% stronger than .060 mil bare EPDM. Fleecebacked EPDM has a tear strength of 39.9N/mm compared to 13.1N/mm of that without the fleece reinforcement, more than 3X the strength. Even bare .045 EPDM rubber, a 1.14mm (.045) thick membrane with no fleece backing, holds a L4 puncture rating
WeatherBond RBR White EPDM is a .060”-thick (1.52 mm) roofing membrane, Ethylene Propylene Diene Terpolymer (EPDM) based elastomeric homogenous roof covering which may be used for new single-ply roof construction and re-roofing or repair applications.

Thermoplastic single-ply roofing membranes are among the fastest growing commercial roofing products and have gained broad industry acceptance for their many performance and installation advantages. As demand increases for heat-reflective and energy efficient roofing systems, thermoplastic polyolefin (TPO) single-ply roofing membranes continue to provide exceptional resistance to ultraviolet, ozone and chemical exposure.

Thermoplastic Polyolefin single-ply roofing. This roofing material can be fully adhered, mechanically fastened, or ballasted. TPO seam strengths are reported to be three to four times higher than EPDM roofing systems. This is a popular choice for "Green" building. It is available in white, grey, and black.[2] Using white roof material helps reduce the "heat island effect" and solar heat gain in the building. However, TPO has changed formulations over the years and each manufacturer has its own mix of "polyolefins" (plastics.) This means that TPO remains largely unproven in real world applications as its current formulation exists today.

PVC (vinyl) membrane roofing
Polyvinyl Chloride (PVC) membrane roofing is also known as vinyl roofing. Vinyl is derived from two simple ingredients: fossil fuel and salt. Petroleum or natural gas is processed to make ethylene, and salt is subjected to electrolysis to separate out the natural element chlorine. Ethylene and chlorine are combined to produce ethylene dichloride (EDC), which is further processed into a gas called vinyl chloride monomer (VCM). In the next step, known as polymerization, the VCM molecule forms chains, converting the gas into a fine, white powder – vinyl resin – which becomes the basis for the final process, compounding. In compounding, vinyl resin may be blended with additives such as stabilizers for durability, plasticizers for flexibility and pigments for color.
Thermoplastic PVC roofing is extremely strong, as its heat-welded seams form a permanent, watertight bond that is stronger than the membrane itself. PVC resin is modified with plasticizers and UV stabilizers, and reinforced with fiberglass non-woven mats or polyester woven scrims, for use as a flexible roofing membrane. PVC is, however, subject to plasticizer migration. (a process by which the plasticizers migrate out of the sheet causing it to become brittle.) Thus a thicker membrane has a larger reservoir of plasticizer to maintain flexibility over its lifespan. PVC is often blended with other polymers to add to the performance capabilities of the original PVC formulation, such as KEE - Keytone Ethylene Ester. Such blends are referred to as either a CPA - Copolymer Alloy, or a TPA - Tripolymer Alloy.
Vinyl roofs are inherently fire resistant due to their chemical composition and have a broader range of fire ratings over common substrates.
PVC has been sold for commercial roofing use for more than 40 years. Vinyl roofing membranes' long life cycle – and the associated lower energy consumption to both produce the raw material and process it into useful products – is a significant factor in their sustainability as a building product.
Vinyl roofs provide an energy-efficient roofing option due to their inherently light coloring. While the surface of a black roof can experience a temperature increase of as much as 90 degrees under the heat of the full sun, a white reflective roof typically increases only 10-25 degrees Fahrenheit.
Vinyl membranes can also be used in waterproofing applications for roofing. This is a common technique used in association with green, or planted, roofs.
It worthy of note that many Green Building organizations recommend not using PVC roofing due to significant environmental hazards from the toxicity of the manufacturing process as well as the noxious compounds released in a fire such as hydrochloric acid fumes and byproducts including dioxin, a potent carcinogen.


Bamboo is becoming increasingly used in building because of its reputation as a green building material. It is fast growing, hardy, and can give a very natural/textural feeling to a space.

There are several methods for curing bamboo: soaking, air drying, and aburanuki are the main ones. Aburanuki (or some version of it) is probably the method we would be using for this project. Aburanuki involves heating the bamboo over a fire in order for the sugars and resins to come to the surface of the bamboo and be removed. It is a technique that was originally used by flute makers. Once the bamboo is cured, it needs to be finished. This can be done by heating the bamboo and applying an oil or fat, or by applying another finish such as natural shellac. We may need to do some testing of the finishes to figure out which ones best stand up to water exposure.

Aesthetically, using bamboo is very interesting because of the beautiful variations in color that you get when you cure it. There is also opportunity to apply finishes for some cool effects. Here are some pictures I can across when brainstorming about ways we could use the bamboo.


Let me know which ones you guys think would be most interesting for the BHome

Front access [SC]
Two options - porch steps, inclined ramp
Both of these can be constructed to fit the B-home's height. The porch steps may be a problem if any disabled individuals are living in the B-home, which is why a ramp would be able to accommodate more people.
However, a guide to building porch steps entry is here: Porch steps

Solar Chimney

The goal of the solar chimney is to increase ventilation within the B-Home by heating air within the chimney in order to force it to rise and pull air through the home itself. Due to the small size of the B-Home, the chimney aperture does not need to be too large, but the specific dimensions will depend on other design elements.

The chimney will ideally push out the back of the B-Home. The solar collector area (facing the sun) will hopefully be a black ceramic or black ceramic gravel, with stainless steel and painted glass being our other options. The side opposite the sun should be whatever insulation we choose to use for the rest of the home – for the sake of consistency. If we choose to use black ceramic gravel, further research will have to be done in procuring it, but below is a location to purchase tiles. Glass/steel are more general materials and may not need to be purchased commercially.

Also important is the fact that the chimney may create an opening for water to run through during storms, et cetera. To help hinder this, we can make sure the opening of the chimney is not straight up, but we will also need to design a cover of sorts. I would suggest using the already-purchased water-proofing material for this part.

Black Tiles: http://www.buytile.com/home.php?main_page=product_info&cPath=4&products_id=10991&szid=256
http://www.nextag.com/black-ceramic-tile/compare-html (easily comparable prices)

Exterior Lighting

Vegetation and Garden Elements

Awnings/Shade Elements

Security (Lock) [SC]

Two major types of locks: key in knob lock and deadbolt lock (other options exist, but they are more extensive and may actually prevent the home dweller from feeling secure, since having too much security equipment could overwhelm them and frighten them)

Key In Knob Lock
Least protection, simple latch that can be slipped open by inserting credit card. Generally only recommended as extra measure of security. [3]

Add security without replacing existing key in knob lockset. Single cylinder opens with key from outside, double cylinder requires key on both sides.[3]

There is definitely no need for a double cylinder deadbolt (people do not need to use a key to exit the B-home. However, based on the above and in the interest of maintaining security, I believe having both a key in knob lock and a deadbolt lock would provide a significant amount of protection and security without being too overbearing (with a chain lock, etc.). Thus, I suggest either a deadbolt lock, or a deadbolt+key in knob combination.

Purchasing options
Some of the possible deadbolt locks that can be purchased are listed below.

Kwikset 99800-087 kwikset [Cost: $37.83]

Single Cylinder deadbolt lock home depot [Cost: $17.10]

Schlage B60 609 Grade 1 Single Cylinder Deadbolt amazon [Cost: $28.00]
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