DIY Internal Solid Wall Insulation

jkgray

Now heading into my 3rd winter in my cold victorian house decided that it was time to internally insulate the solid walls. (external insulation is a non-starter as we're in a conservation area)

The options seems to be:

Sempatap

http://www.mgcltd.co.uk/Products/Thermal_and_Acoustic_Insulation/SEMPATAP_THERMAL/

Given it is a wall lining, just paste it to teh walls and then wallpaper over

Use insulated plastboard

Something like this:
http://buildingmaterials.co.uk/Insulated-Plasterboard/BG-Thermaline-Super--Insulated-Plasterboard/p~695~026_157_003-Gyproc-Thermaline-Super-Insulation-Board-2400-x-1200-x-50mm.html

Presume could just dot and dab this directly to exisiting sound plaster walls.

Necessary to mechanically fix the same - say using http://buildingmaterials.co.uk/Insulated-Plasterboard/BG-Thermaline-Super--Insulated-Plasterboard/p~1026~034_034_022-GYPROC-NAILABLE-PLUG-110MM-BOX-100.html?

Spacetherm

http://www.proctorgroup.com/Products/ThermalInsulation/Spacetherm.aspx

Assume same as insulated plasterboard but get much greater results for much thinner board.

Can't actaully find anywhere that sells in on the net though.

Also suspect it would be v expensive - saw one mention on net of £500 for 10m2

Superfoil

batten the walls

Staple something like this:
http://www.progressiveproducts.co.uk/shop/page_product/item_113/index.html

to the battens

the put another set of battens over to provide recommended airgap the attach 'normal plasterboard.

Comparative insulation values?

Sematap said to have thermal resistance of 0.194m² K/W. Think they say that resistance of wall with sempatap fitted 0.67 (units?) and U value is 1.49 W/m²K.

Foil is said to have R value of 9.6.

Foam on plasterboard is said to have Thermal Conductivity: Super phenolic foam 0.020W/mK to 0.022W/mK (dependent on thickness of foam) - does this equal R value of 2.25 based on 45mm of foam?

Spacetherm said to have K factor of 0.013 W/m2K. don;t know thickness so can't work out R value?



Anyone have experience in this area? Thanks

jkgray

So thsi thread can also act partly as a reference for others there is an interesting thread here:

http://www.navitron.org.uk/forum/index.php/topic,4507.0.html

Though given it is from 2008 the material costs will have chnaged and so teh cost/benefit comparisons may not longer be valid.

A.Penny.Saved

That Gyproc Thermaline Insulated plasterboard seems very expensive and I cannot see what thickness it is, all it says is 2400 x 1200 x. How or why would anyone purchase not knowing how thick it is? It could be 10ft thick for all I know, would you put that in your home if you could get it through the door? :rotfl:

There is a lot of disagreement on using insulation internally, some people claiming that it can cause problems due to dampness and harm due to associated mould growth.

I have thought about such insulation myself but costs are a problem, not being able to afford to do the whole house and the disagreement on it's benefits are another.

There isn't much concrete, pun intended because my home is built of concrete, evidence either way. Internal should be better than external as it directly prevents warmth escaping the inside whereas external insulation only slows it from reaching the cold outside. It doesn't stop the wall absorbing heat and that getting lost.

The R value you calculated looks about right.

You put a great deal of info into your post, too much for most people to read IMO. It overwhelms people.

jkgray

A.Penny.Saved wrote: »

That Gyproc Thermaline Insulated plasterboard seems very expensive and I cannot see what thickness it is, all it says is 2400 x 1200 x.

The last figure has been cut off the page quoted, but from the previous page listing the range http://buildingmaterials.co.uk/Insulated-Plasterboard/BG-Thermaline-Super--Insulated-Plasterboard.html you can see it is:

9.5mm plasterboard
Backed with 40.5mm brown coloured phenolic foam

prosaver

jkgray wrote: »

Now heading into my 3rd winter in my cold victorian house decided that it was time to internally insulate the solid walls. (external insulation is a non-starter as we're in a conservation area)

The options seems to be:

Sempatap pictures are untrue

Visual Image Before Thermal After Thermal
have a look at next doors house (on the left) its letting the heat out also ....and when the original house gets insulated ...by magic next door stops letting heat out ...........scam
:rotfl: :rotfl: :rotfl:

A.Penny.Saved

Sempatap is garbage and I wouldn't put it in my home if they paid me. Imagine the holes in your wallpaper every time you knock it with something!

I have noticed the thickness in the url, it says 50mm but nothing on the page in two different browsers.

prosaver

I put blown vinyl on the ceiling and walls to hid the cracks and I was surprised that it kept the heat in as we were to on a single cavity wall

prosaver

http://uk.answers.yahoo.com/question/index?qid=20090209093641AAVSpIG
this might help.

jkgray

prosaver wrote: »

http://uk.answers.yahoo.com/question/index?qid=20090209093641AAVSpIG
this might help.

Thanks.

Given the answers at 2 yrs old however, I think the options have come on a lot since then in both options available and affordability.

Johnjohn

From a technical perspective external insulation is usually the best option because you can get high insulation values and you don't get problems with cold bridging. The problems are the fact that it can look ugly and the fact that it can trap damp. Decent internal insulation takes up lots of space - although new developments such as aerogel insulation and vacuum insulation could make this less of a problem - but for now you are looking at losing at least 50mm on each insulated wall to get a decent insulation value. I have heard of good results with Sempatap, but clearly you are not going to get the same insulation effect as thicker forms of insulation. If you have an unpainted exterior wall you could consider making it waterproof to ensure that its natural insulation value is maintained even when it rains (see video on this page - http://safeguardstore.co.uk/damp-proofing-and-condensation-control/stormdry ) - this sort of approach could be combined with Sempatap applied on the inside wall. In theory the thicker and more porous your wall is the better the insulation value it has if you can keep it dry.

Johnjohn

Oh yes, there is a big debate going on in the insulation industry about the most appropriate way to measure insulation values for traditional air entraining insulation products (rockwool, foams etc...) vs foils. The effectiveness of different forms of insulation depends on the type of heat transfer (conduction, convection, radiation). That is about the extent of my knowledge I'm afraid, but the end result is you can't really compare U vales of foils with those of other forms of insulation (I think).