Breathable insulation options under stone flags ?

[masochists-r-us]

Hi everyone,
Would be interested the views of the forum as to how helpful breathable insulation material such as clay pellets would be to reduce heat losses from under the stone flags we're about to lay. We know many of you out there have them laid straight on the earth, but my other half is keen to meet modern standards where we can without compromising breathability.
Any other suggestions for appropriate insulation materials would be appreciated.

 

[AMc]

I can't help much beyond mentioning build regulations probably apply unless they're trumped listing - in which case LBC applies. As relaying the floor is significant work on the thermal element (aka the floor) you should almost certainly meet the minumum requirement of PartL1b of the building regulations.
http://www.planningportal.gov.uk/england/professionals/en/1115314231799.html

There have been plenty of threads here but you should also browse the Green Building Forum - some of the posters will be familiar e.g. http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=4049&page=1#Item_0

 

[Flyfisher]

Gareth's recent post on building regs suggests that the requirement to upgrade to latest regs is being dropped in the next release of the regs, which sounds sensible in the context of older properties as it gives people a wider choice of options. Of course, there's also the little matter of how a BCO would ever find out that an internal floor has been relaid in the first place.

 

[AMc]

I don't profess to understand the in's and out's of dropping the consequential improvements clause other than it was also dropped from the 2006 revision.

AFAIK The 2006 revision requires you to upgrade thermal elements to meet the current regs. I can't copy/paste from the PDF but the bits I believe apply are section 4A -1 on page 7 and paragraph 54 on page 23 http://www.planningportal.gov.uk/uploads/br/BR_PDF_ADL1B_2006.pdf

I think it's safe to assume that you would still be expected to make improvements where practical and breathable insulation in the floor should do no harm.

Interestingly reading the Building Control guidance it states that special considerations apply if the building has special architectural or historic value - but doesn't specifically indicate listing. I'm sure you can use listing as evidence of this, but it suggests some wiggle room if you were able to show an unlisted house was 'special' too.

Of course, there's also the little matter of how a BCO would ever find out that an internal floor has been relaid in the first place.

You could argue the same thing applies to changes to a Listed building without Listed Building Consent. I've never believed either is acceptable, but I don't want to drag this thread off topic.

 

[Flyfisher]

I agree about 'making improvements where practical' to the thermal performance when undertaking such works, but that's not quite the same thing as bringing things up to the levels of the current regs, which might impose unreasonable demands on a period property with the result that nothing is done at all. It must surely be better to allow improved thermal performance by any amount than impose all-or-nothing regulations.

I take your point about doing the work without consent or approval, but sometimes the rules don't make sense - like insisting on thermal performance to the latest regs if 'major refurbishment' is undertaken. Sometimes this won't be possible with sensitive methods appropriate for an older house, in which case the dilemma is to do nothing or do something sensitive that will improve things even though it won't meet the actual regulations. Hopefully, that's now being recognised, hence the relaxation being proposed in the changes Gareth mentioned.

 

[yamin]

? Sheepswool?

Interesting thread here

http://forum.downsizer.net/viewtopic.php?t=38819&start=0

 

[chuckey]

Are your flags "breathable", mine are not, only the lime mortar ~ 2% of the total area. I wonder how you are going to lay flags on sheeps wool?
Frank

 

[rebeccac]

We are laying a limecrete slab the setting old bricks into a sreed bed over this.We dug out the earth to about 3 ft levelled and compacted , put in a single layer of stones (large limestones) then over this is gravel over this will be limecrete and bricks.