Single leaf with external insulation

joeirish

So how does single leaf concrete block with external wall insulation as a build method compare cost wise with other methods such as timber frame or wide cavity for a low energy type build (external wall u-value around 0.2 or less). So many different figures to think about, my head hurts

And does anybody know of competent builders in the Limerick/Clare/Galway areas who could do this for a new house? PM me if you do.

Thanks

sas

Single Leaf with external insulation is considerably more expensive than wide cavity.

I built with single leaf and ewi. I'd go with wide cavity if I had my time again on a financial basis if nothing else.

Timber frame is harder to quantify as the quality varies all over the place along with the price. In my case if I had gone with block outer leaf and good quality tf, it would have compared similarly to the single leaf with EWI.

That was 3 years ago though.

Go with the wide cavity...

archtech

I've found the gap to be narrowing and very little if using a conc first floor and bearing the slabs on 215 solid blockwork.

joeirish

Thanks for the replies so far. It seems to be so difficult to get a meaningful quotation from anybody except the timber frame builders. I have had a lot of very detailed quotations from the TF companies but when I tried to get comparative prices for other types of build I just get vague response. Poroton? Price for the blocks but nothing useful on labour costs (do they think I'm going to put it up myself?). Single lead with EWI? Well we'll see. One builder has said he will give me a quotation but otherwise just vague figures of approximate cost per sqm for the insulation. It's like dragging teeth. Is the construction sector recession really over and are all these people really so busy they are not interested in even giving quotations? I know it's a pain to have to do up a quotation (I've been there and done that in another area) but as a customer for a new house I am not about to engage builders based on some vague idea of what it might cost. I have detailed architect's plans, full planning permission, specs for u-values, airtightness etc. Just want some prices so I can decide and get going. Sorry for the rant but if there are any builders out there who are interested in quoting then please PM me. I live in Clare.

PROJECT K

Hi there, i am currrently building EWI method (215mm block on flat with external insulation) and while i find that detailing is relatively simple and programme is quite quick, it isnt the cheapest option (i am finalising EWI contractor now and its still a very specialised area - the render and reputable contractors are expensive) - probably really only worthwile considering if you are aiming for lower than 0.12 or 0.10W/m2.K as i am. For sub 0.2 U-Value, i guess down to around .15, i would defintely run with wide min. 250mm cavity either with a rigid EPS platinum board or pumped with grey bead (make sure to use low conductivity wall ties in either case) - there are a few good examples of this type of construction out there and a lot of guidance on how to get the details right.

I would be quite confident this will beat any TF or EWI price and be most economical to meet your targets...

If i am honest, as the reality of a wayward budget hits me :eek:, i would have opted for pumped wide cavity and made compensations elsewhere!!!

joeirish

ProjectK thanks for the reply. Very helpful. So now I might be looking for a builder in the Clare area who would be willing to quote for a wide cavity build. I might start another thread cos this one has the wrong title. But if anybody has suggestions then please PM me.

Thanks

BryanF

joeirish wrote: »

But if anybody has suggestions then please PM me.

Thanks

There you go

joeirish

BryanF wrote: »

There you go

BryanF not sure what you mean? No PM received?

Thanks

BryanF

misread post please ignore

thebackbar

just resurrecting this thread, what are people thoughts of Single Leaf with external insulation versus wide cavity, is ewi still that bit more more expensive ? if anyone has recently got prices for ewi could they pm them to me ? thanks

BryanF

thebackbar wrote: »

just resurrecting this thread, what are people thoughts of Single Leaf with external insulation versus wide cavity, is ewi still that bit more more expensive ? if anyone has recently got prices for ewi could they pm them to me ? thanks

I will and have used Ewi but is Longevity of Ewi (v block) the real question?

SeaniO

Hi, I'll try and resurrect this tread also.
I'm currently thinking of building a single leaf house with the following...

Cavity blocks(Filled with expanding insulation) - External insulation - Render.

I'm wondering if I can save money on the blocks and have more insulation.

Is this a crazy idea or what?
Has anybody got opinions?