Saturday, February 25, 2012

Energy efficiency in Buildings - Roofs

From this year we are looking into 'Energy efficiency' in buildings and how to apply it. Being what it is, some people still battles with that idea. As a plans examiner I have to narrow down the possible 'ifs' and the “not’s”...
To put this in perspective, the minimum requirements and that also applies the 'deem-to-satisfy' rule.

So my question would be: “What is the minimum requirement to insulate a roof?”
I have people still up to date specifying 'asbestos roof sheets' although this material has been substituted by various products which one is fibre-cement roofing.

Coming back to insulating roof spaces, we have learnt that a R-value of 3,7 must be achieved throughout the roof design to prevent solar heat gain within the building. This can only be achieved by a combination of two products namely 'Think Pink Aerolite & Reflective foil also known as Sisalation".

These products can be found on the following links: http://www.isover.co.za & http://www.sisalation.com
For those specifying the product, make sure its the correct one as you take responsibility for what you specify.
See below pictures taken when installation took place.

Think pink aerolite being installed above the ceiling boards.

Sisalation being installed to the underside of the rafters.

4 comments:

  1. please advise how do you convince owner builder /contractor etc to use materials as specified because when plan is approved one is seldom consulted not even by the area building inspectoe

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    Replies
    1. You as the consultant must sell the product to enhance the design. Most important, you are designing for the owner and would like the products used to benefit them as well as your design. In the long run, do you spend the money and live a happier life in better conditions or do you prefer using something cheaper with less benefits and have to replace or redo it within 5 years. You decide how you would approach your client. It is not how much it costs but how efficient it would be. It is also your service to the clients to keep up to date with your products and to advise them what is more efficient. The area building inspector would only ask for what was specified and approved on plan therefore you must know your products you are specifyiing.

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  2. another concern is the lighting especially where dome lights are concern and window specs certain owners tend to buy whats suits them without informing draftsman

    ReplyDelete
    Replies
    1. This question refers back to the previous one and therefore I will advise you once again to specify your products. Most likely the owner doesn't see any specification and therefore specifies anything to the builder. A good draughtsman that specifies his products on his plan the way he should doesn't even need to communicate to the builder as the plan would act as the communication file between them. Sit down with your client and discuss these challenges. You, on the other hand, are the one that signs off the forms (SANS) stating that you take it upon yourself to check that what's on plan appears on site. Take note what you specify and how you do it.

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