Sempatap Thermal solid wall insulation

Furn462

I'm currently in the first steps of doing up a house which has solid walls throughout. I've had a building survey done and they recommended getting some solid wall insulation, either internally or externally. Having dug around a bit I've come across a product called Sempatap Thermal, which appears as though it can be applied, internally, directly to the already plastered wall and then decorated. Does anyone have experience of this product? My first step will be to apply to one bedroom. A few queries I have:

1) The bits I've read suggest it is easy to DIY - is this true?
2) The insulation is only required on two of the four walls - will there be a difference in finish if I merely skim the other two?
3) The skirting boards need replacing - do I put the new skirting on and then attach the Sempatap, or is the skirting ok to go over the top of the Sempatap?
4) How do I treat the radiator and plug socket issue? I guess the plug socket issue is fine, it can just sit over the top of the Sempatap. But can a radiator be hung on top of this product?

Any help or advice that anyone can give would be greatly appreciated.

Thanks

Andy

fatbikersbouncebetter

seems it makes the wall feel warmer, though its not very thick, so I am not convinced it is sooooo good. Good DIY skill are probably enough. Good luck/

telsokari

just wondering if you ended up using this and if it was any good?

I've been considering it. Any feedback would be great

Thanks

societys_child

Have a read here

Is it really over £225 a roll?

savemoney

Its expensive for what it his. I got a quote from BG via EST for £1600 for a 3 bedroom house. But the alternative is even more expensive there are two choices internal wall insulation or external wall insulation. Also sematap has a life span of around 10 years so I seem to recall. There is little or no help for people with solid walls we left to rot unless fuel bills get so high it might be worth it

Furn462

I didn't go for this in the end. Reason wasn't anything to do with the product, but the quality of plaster - it had mostly blown so needed to come down anyway. I ended up hacking off all of the plaster to the brickwork, battening and using Kingspan Kooltherm K18. Not cheap but gives me a U-value of 0.3, which I think outstrips what the Sempatap can do.

I agree that there isn't much in the way of grants/assistance for older style properties. It seems everything is for cavity wall only, so if you're in a solid walled house you've got to foot the bill yourself. External insulation is more effective I believe but obviously means you end up with a rendered house, which isn't going to be everyone's cup of tea. Problem with the internal is the loss of floor space. For me hacking off the plaster, battening and boarding with 50 + 12.5mm lost me only about 1 inch off the floor space.

The_Pedant

Am I right in thinking that building control needs to be involved when replacing more than a certain percentage of external plaster or plasterboard? Not sure what the percentage is.
Went for the battens+overboarding approach myself. Sure the kingspan will give a much better result.

MX5huggy

The_Pedant wrote: »

Am I right in thinking that building control needs to be involved when replacing more than a certain percentage of external plaster or plasterboard? Not sure what the percentage is.
Went for the battens+overboarding approach myself. Sure the kingspan will give a much better result.

Yes building control "should be involved" the numbers are if the area is greater than 50% of of the surface of the individual element. ie if you take more than half the plaster off a bedroom wall you should up grade it.

Or if the element is 25% of the total building element.

Its all on page 17 onwards of building regulations part L1B (use a search engine to download it)

There are a couple of get out clauses if its going to take up too much space or not save enough money, but you still hav eto do something.

Of course building control don't do random inspections of plasters.

greenlaws

Be careful. A solid walled building needs to breathe. If you stick a load of junk onto the wall, it wont breathe and the house will end up wetter than before, mainly from condensation related problems. This is a huge issue, too hard for one post. In short, the solution is this ...
Clean the wall of anything back to bare brick.
Use a steel frame system - from Protektor Uk, or British Gypsum system
This allows pipes and wires to run behind
Step it off the wall by about 20mm to allow a breathable air gap.
Insulate - but you must use sheepswool - NOT mineral wool which suffers from condensation
Then plasterboard as normal.

Then google the latest SPAB research on insulation of old buildings - they have just released a superb research report on this - in which this system is referenced. I'd include a link, but as a newbie I'm stopped from putting links up - which is a pain... but maybe mods will let me.. Mods - please email and I'll put the research link up for all to see the effective u vales.

Warning - most of the systems sold by independent companies are snake oil - DONT buy them.

littlesnuggy

As an alternative to internal or external cladding/lining, I've heard good things from surveyors about this new 'cream' application http://www.properteco.co.uk/wp-content/uploads/2011/12/Thermalogix-from-PropertECO.pdf

It won't insulate as much as the Kingspan type stuff, but claims to save up to 9% of heat loss and I was told it would cost about £700 to have it applied to a standard semi-detached house (by someone else).

km1423

Littlesnuggy, I would be interested to know results if you go ahead with this. I live in a 1900 Semi D. No room really inside for rigid insulation. Will use something similar to Wallrock inside on top of thermal plaster. This product on the outside as an additional benefit.