Thinking of this for our solid wall, ex-council semi. Anything in particular I should be asking for / making sure they do etc, before they come & give me the hard sell ?

It can be expensive, but there is a lot of decent funding about now (since the beginning of the year), depending on the spec you go for you could be looking at 70% ish funding (funding is called ECO).

Be careful of a material called phenolic, starting to get some reports of it needing repairs/replacement after a few years. EPS or mineral wool are seen to be better now. Silicon or render/dash are cheaper, but brick slips are available which would push the price of a job up and lower the %age of funding contribution.

Good idea to team up with your neighbours if they’re also living in solid wall properties, can get some cost savings through economies of scale.

Of course I’m assuming you want external insulation not internal. Internal involves quite a bit of upheaval and would cut down the size of your rooms marginally.

We worked somewhere where they used wood fibre type board and rendered. Quite green and very good insulator.

I worked for a company installing internal insulation for solid walls, and doing all the associated work.

If you want any information regarding internal work, let me know.

You want to look / ask about detailing ie how they insulate window reveals etc. Bugger all point insulating the facade if that detail is neglected. Also want to make sure its not too thick that stops window / trickle vent function. Any surface mounted cabling.

Hammerite, not sure what you mean about Phenolic boards needin to be replaced ?

Celotex/Kingspan are Phenolic boards, and they have are designed for “the lifetime of the building”

Thanks. Yes, external insulation. We have a conservatory, so keen to see how they work around that. Also the gas pipe was replaced a while back, & runs up the outside of the end wall. Will they just go over the pipe ?

if it is a solid wall then either the external insulation must more vapour open “breathable” than the wall itself or a internal vcl vapour control layer must be installed.

basically this means to comply with regulations eps, celotex etc need to have a floor to ceiling membrane installed

this isn’t in a lot of the manufacturers info but is in relevant British Standard It’s conveniently forgotten

I work in the industry,for a manufacturer. Second the advice regarding phenolic. For cost v performance graphite coated EPS works well, or if you can afford it use PIR.

Most of the rendered systems have a synthetic typically acrylic or silicone finish which depsite what many manufacturers tell you about claims of “self cleaning” or otherwise which will eventually need to be recoated.

Go for a mineral render or dry dash finish if you want it to last or want less amintenance.

Look for an installer who is PAS 2030/green deal acreddited. Many will be starting to offer the 25 year SWIGA guarantee. Ideally look for an installer who is a memebr of INCA or the NIA.

Celotex and kingspan have phenolic products, they also have products using other insulants.

We’re getting reports from some of the EWI installers we work with and some housing associations that the phenolic solutions are needing to be ripped out and replaced. One of the installers is refusing to work with phenolic. Might be designed for the life of the building, doesn’t mean it’s turning out that way. I need to get more info on what the exact problem is, I’ll let you know what they say.

Celotex is PIR,Kingspan is phenolic.PIR is cheaper than Phenolic.
Takiswawa,Gas pipe generally needs to be accesible so trunking,with a lid and vented.

Not a good idea to bury a gas pipe in insulation or render for obvious reasons…………..

Ideally if it is spaced off the wall,then ou can get insulation beihnd it otherwise it will act as a cold bridge.

Not much you can do about the conservatory other than work round it and accpet that,there will be an area of compromise.

X-post with JGG. Do you know what the issues the installer I was talking to might be referring to with phenolic?

Hammerite,there have been “issues” with shrinkage of the boards which can then cause the overlying render to crack, or will reflect as undulations underneath.

Ah ok thanks.

If you want to know more about EWI let me know and I can email some ueful info.

At Openreach we’ve just had emails about external insulation. Apparently some stuff can’t take the weight of a ladder leaning against it, also installers have been going straight over phone cables run round the building, and where overhead dropwires are fixed, they are insulating/rendering over/around them so you can’t replace the dropwire…the wire just disappears into the render!

No secure fixing = no phone service until a solution is found. And from the sound of it, its down to the home owner to provide a secure fixing, Openreach don’t appear to have a solution at present…hard to fit an expanding eyebolt into insulation 🙁

We often have fixing issues on large scale social housing refurbishment projects. The installer will often put a timber block recessed into the insulation to fix too,particularly for satellite dishes.

Alternative is fixing through the insulation with a sleeve and and then sealing with a mastic.

Very light fixings can be surface mounted but you should always check with the system supplier. We have some standard fixing details showing the various options.

Ladders are Ok if you avoid the point loads by resting it against a board. Good installers should provide this information to the client.It`s certainly freely available form the system manufacturers.

There was a posting on timber cladding over insulation recently…

http://singletrackworld.com/forum/topic/cladding-a-house-with-wood-anyone-diy

Hammerite, Google “Phenolic insulation shrinkage”. 😉
For cost effectiveness, we tend to use mostly graphite coated EPS,these days.

Dependant on the background structure in some circumstances the additional thickness isn`t always much more than phenolic.

Would this be the same for an internal wall? I’m taking a double garage that had one half converted. The converted room is damn cold so was planning on just sticking some celutex up. Is that OK?

As there are folks here in the industry, can anyone get me some very cheap 30mm insulated plasterboad, i only need 9 or 10 boards 🙂

Openreach don’t appear to have a solution at present…hard to fit an expanding eyebolt into insulation

Get a longer drill and bolt?
*wonders how much he can charge Openreach for his excellent advice that assists solving a ‘difficult’ problem*