Nudura vs Nudura Plus...

[Mulberry View]

We're swaying heavily towards Nudura for our ICF build. Their supplier, who have been very supportive so far, has recommended the standard Nudura blocks and suggested that, in general, the extra investment in their Nudura Plus blocks is not worthwhile in terms of energy saving vs investment. They say we shouldn't focus too much on miniscule U-Value improvements.

 

On the other hand, our architect, who has no ICF experience is instead saying it's all about the U-Value and we must do as much as possible.

 

This is to be our forever home and although we do not have an 'open chequebook', we do want to get it right.

 

Any thoughts on this?

[willbish]

Sounds like you are at an important crossroad for your build.

 

If you decide to chose a lower (or lowest) Uvalue ICF block you could be embarking down a road where you will be focusing on airtightness, thermal bridging & 3G windows. Sounds like your architect is up for it.  

 

ICF (poly) is inherently air tight so you've ticked that box and if you are going for an insulated raft, thermal bridges can easily be kept to a minimum. Last box to tick is excellent U-values. Then you'll have a property that will be especially easy to heat and cool (amount of glazing dependant!). 

 

On the other hand if you're not so bothered about designing out thermal bridges and air tightness then the standard Nudura block may be the best bet.

 

I know someone with the fattest Nudura blocks on the market. Their heating system is pretty much non existent. Not even UFH, just a single electric heater in the main living space is apparently enough. This an extreme example, but the point is if you increase the insulation levels (and airtightness and thermal bridging) you can reduce the complexity and cost of a heating system.

 

Personally I have an Isoquik insulated raft and Logix ICF which is 70mm inside and 203mm outside. Ive chosen wet UFH on the groundfloor for heating and cooling with an ASHP

 

 

Edited July 30, 2021 by willbish