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R4 or R5 Roof Insulation?

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    Hi Guys

     

    Advice please - R4/R5 for roof insulation? We have double glazing and was wondering if we need the maximum...

    We live just on the cusp of foothills (Stonyfell) so it is colder than down the bottom of our road so to speak..

     

    We do not have insulation in our house atm

     

    Thanks for reading and for all those who commented on my previous posts on this subject.

     

    Fiona

     

    PS does anybody know how much 12 'downlight covers' should be? got a quote of $264 inc GST thought this was expensive...the remaining lights are LED

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    Guest Guest12727

    I would go for the highest possible - it will pay back in time. Remember you probably are a bit colder in winter and this will reduce heat escape.

     

    What are downlight covers - are they covering halogen lights?

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    Thanks for your reply - yes the downlight covers are for the halogen lights. You must use these if you have halogen lights but not LED

     

    The guy that has just quoted me recommends the R4 hence my question..although R5 is thicker he said here we just need R4...

     

    I too agree with you the highest possible.

     

    Cheers

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    Guest Guest12727

    Mmmm, I have looked up some info - rather than spouting off the top of my head. Lochiel Park guidelines show roofs lined with foil plus bulk insulation of 3.5. I don't know what this gives overall with the 2 combined, but maybe 4 is OK.

     

    The current SA building regulations are R3.2.

     

    The sustainable living people all talk about the overall thermal mass of the building, so orientation for passive heating / cooling, shading etc all come in the mix.

     

    I also found something that says as you go higher you get diminishing returns, and you may be better spending the extra money elsewhere (perhaps in replacing all the halogen bulbs for LED)

     

    You can get an energy assessment done to help channel your money in the best way. There is a guy in the Hills who specialises in updating older homes for energy efficiency.

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    Hi Guys

     

    Advice please - R4/R5 for roof insulation? We have double glazing and was wondering if we need the maximum...

    We live just on the cusp of foothills (Stonyfell) so it is colder than down the bottom of our road so to speak..

     

    We do not have insulation in our house atm

     

    Thanks for reading and for all those who commented on my previous posts on this subject.

     

    Fiona

     

    PS does anybody know how much 12 'downlight covers' should be? got a quote of $264 inc GST thought this was expensive...the remaining lights are LED

     

    I wouldn't bother having insulation put in unless you replace the downlights with LED ones first. According to our builder the current regulations mean the insulation has to be cut away quite a distance from the lights, leaving you with big holes in it. The downlight covers may negate this, I don't know, but I would personally want to research this first if I was you.

     

    With the insulation find out how much the R5 would cost before making a decision. We have just built a house with R5 insulation in the roof and R3.5 in the walls. (And UPVc double glazing). We haven't moved in yet so no curtains or air con or anything but we were in there today and it was significantly cooler inside than outside. The builder put it down to the insulation in the roof. I'd be tempted to go as high as you are happy to pay for.

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    In fairly basic terms try and follow these points on very approximate payback terms.

     

    Basic loft insulation, generally pays for itself within 2 years. Foils also can reflect out heat as well as keep heat in.

    Wall insulation, more difficult to install but say cavity fill or inner or out insulated render, circa 20 years to pay back.

    Floor insulation 20-50 years to pay back

    Double glazing circa 70 years to pay back, would be even more in Australia as not as cold. Therefore renew glazing for more than just thermal gain reasons as they take ages to pay back.

     

    Get the best loft or roof insulation you can and make sure it remains a ventilated area to avoid condensation.

     

    LED lights run at a much lower temp so insulation can be closer. I would always recommend down lighter hats or covers as theses physically hold the insulation away from the down lighter therefore meaning it does not overheat. Also remember electrical fittings degrade with time so naturally run hotter and I have seen a few fires in properties from overheating down lighters causing quite a lot of damage. Also be aware if LED lights fail they should trip the fuse on the consumer unit or main board.

     

    Best of luck with it all. All the sort of improvements we will be making when we purchase.

     

    S..Chartered Surveyor and Project Manager

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    I wouldn't bother having insulation put in unless you replace the downlights with LED ones first. According to our builder the current regulations mean the insulation has to be cut away quite a distance from the lights, leaving you with big holes in it. The downlight covers may negate this, I don't know, but I would personally want to research this first if I was you.

     

    With the insulation find out how much the R5 would cost before making a decision. We have just built a house with R5 insulation in the roof and R3.5 in the walls. (And UPVc double glazing). We haven't moved in yet so no curtains or air con or anything but we were in there today and it was significantly cooler inside than outside. The builder put it down to the insulation in the roof. I'd be tempted to go as high as you are happy to pay for.

    Have you had a look at shipping from UK.......http://www.ebay.co.uk/itm/JCC-Lighting-Down-Light-Firehood-JC93001-180mm-x-150m-/160587427851?pt=UK_Light_Fittings&hash=item2563c1b00b

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    Hi Guys

     

    Advice please - R4/R5 for roof insulation? We have double glazing and was wondering if we need the maximum...

    We live just on the cusp of foothills (Stonyfell) so it is colder than down the bottom of our road so to speak..

     

    We do not have insulation in our house atm

     

    Thanks for reading and for all those who commented on my previous posts on this subject.

     

    Fiona

     

    PS does anybody know how much 12 'downlight covers' should be? got a quote of $264 inc GST thought this was expensive...the remaining lights are LED

    http://www.ebay.co.uk/itm/JCC-Lighting-Down-Light-Firehood-JC93001-180mm-x-150m-/160587427851?pt=UK_Light_Fittings&hash=item2563c1b00b

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    Thank you all for your input - some very useful info..

     

    Yes NicF i did have a quote for R5 as well - in my mind I had decided about the R5 but when the guy came out today he recommended the R4 as he said he rarely does R5...it just got me thinking again..

     

    Cheers everyone

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    Jimmyskinner, to be honest a bit of ducting would also do the job so long as circa 1 ft long, clears light fitting circa 50mm round its perimeter and no insulation is put over the top. The open top will allow the heat from the light to dissipate which is better as fully enclosed caps tend to be for party floor structures.

     

    S

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    Guest Guest75
    Does reflective insulating paint on a roof help much?

     

    I asked about heat reflective paint for our garage door at our local paint store last year. Blooming thing does get hot.

     

    I was told that it had all been withdrawn due to health concerns with the ingredients??? Dunno if any painter on here can back that up?

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    Even in UK protection is given to a lot of roof finishes ie the stone clippings on flat roof finishes are to reflect heat hence why they are white or light natural colour. Yes light colour paints do help however not sure on specific paints however may have had a lead content otherwise oil based paints also seem to be out of favour.

     

    S

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