Should the ducting of the MVHR system in a cold attic be insulated?

ray o

Hi,

I am nearing the completing of a renovation of a 3 bed Semi-d that included a new MVHR system. The attic space is used for storage so not insulated. I assumed the ducts in a cold attic space would be insulated as standard so when I queried if this would be done when commissioning the system I was told that the builder would normally do it if required and so it would be an extra charge if they have to do it.

There was no mention of this in the initial consultation so surprised they would try to charge extra.

Should they be insulated and if so should they be charging for it?

Biker1

Yes absolutely they should be insulated. Building Regs state clearly that any ducting in a cold attic space must be insulated with a min of 25mm foil faced insulation with a thermal conductivity of 0.04w/mk. Sadly this rarely happens and just attic insulation thrown over the ducts seems to be the norm.

ray o

https://www.boards.ie/discussion/comment/123959300#Comment_123959300

Now that you mention it he did say something about throwing attic insulation over them.

listermint

Takes very little effort to wrap these pipes especially for that small a space. I'd even do it yourself if they're unwilling. However a good installer shouldn't be leaving them that way . It causes all sorts of problems with condensation in the pipes plus it increases the temperature range of air in the pipes which is exactly what you don't want.

ray o

https://www.boards.ie/discussion/comment/123959399#Comment_123959399

No issue doing it myself if it comes to it. Can you recommend a supplier of that insulation?

listermint

https://www.boards.ie/discussion/comment/123959538#Comment_123959538

I've used BPC for all my equipment. Can't fault them.