Underfloor Heating.

[tumbledown]

Now that my differences with the CO have been settled and she has seen the error of her ways (well, thats my version of events anyway), I've turned my attention to the floor.

We have removed the concrete floor to reveal a much older floor, which is brick in one area and pamments in another. Unfortunatly, its not in very good condition and beyond restoration. I've discussed it with the CO, and she agrees it should be covered up, but with a breathable floor. The proposal is to use rammed chalk over the existing floor and finish with pamments. The Building Control Officer is also okay with this plan.

However, we have been concidering underfloor heating. The problem being, is I'm not sure it is really suitable in this situation. The main reason I want to do it is to cut down the number of radiators. One problem is I don't really want to raise the level of the floor very much. But I guess you need some sort of insulation to stop you just heating up the old brick floor and getting much benefit from the UFH. This is a timber framed house built in 1550 (ish) and so existing bricks are just laid straight on clay floor.

I guess my questions are:


1) Would the CO object?
2) Would it be an efficient source of heat?
3) Would you recommend gas/water system or electric?
4) What would be the minimum depth of the finished pamment floor be in
relation to the existing brick floor (ie, taking into account some kind
of insulation plus UFL, plus chalk, plus pamments?

Any comments, advice etc would be most welcome!

 

[Nemesis]

Be nice to her. It's a bloody awful job.

Have look at

http://www.newbuilder.co.uk/forum/index.php?DATEIN=tpc_ciruuvyev_1127472078

and

http://www.limecrete.org.uk/limecrete_info.html


http://www.ihbc.org.uk/context_archive/90/henry1/Context90.htm


http://www.mylinkspage.com/greenbuilder.html


Just to start with...


and of course

http://www.pamments.co.uk/


Whether or not it would be acceptable is another matter, depends really on your CO...

 

[tumbledown]

Thanks for the links Nemesis. Actually, the pamments from Norfolk Pamments were the ones I had my eye on - they look just the job.
I heard through a 3rd party that the CO thinks I'm "well meaning but a bit gun-ho!", lol. So, I want to suss out the UFH before raisng the subject.

 

[Nemesis]

Maybe she's got a point you know... I appreciate that you need to get on, her job is to protect history... she maybe has a fair bit of expertise, and isn't as barking as you first thought.

If what you have existing has to be covered, then a POSSIBILITY is to record then remove and put in something else.

BUT... consider it all carefully, cos when it's gone it's gone...

However... the other half did go on a SPAB course about lime and UFH heating earlier this year. Where historic fabric isn't being destroyed, it's not a bad idea.

 

[tumbledown]

Mmm, I think we better agree to disagree on the CO. Also, I think she would have my guts for garters if I removed the floor. I've had the whole house recorded by a historian called Leigh Alston. He helped to smooth things over as his knowledge is much greater than hers and I soon realised that she had great repect for his opinion. He convinced her I hadn't done any damage. Apparently local authorities often call him in when they need an expert opinion. Turns out its quite an important building - more so than they thought. The listing description is a joke too - they described the front door as original 16C - turns out it was knocked together in the 1960's from some old blanks and dado rail!

 

[Nemesis]

Listing descriptions - yes they can be erm ... interesting.

Nothing to do with your CO however!

Expert opinion - hmmm. Sometimes it's a case of in the world of the blind etc!

But in your case...

so be gentle with the building!


http://comm.uea.ac.uk/press/release.asp?id=131

 

[tumbledown]

I take your point about experts - but in this case he did seem to know his stuff. Sounded god anyway!

As far as the building goes, I'm like a pussycat with it compared to how it's suffered in the past - I can almost here it saying "thank you"!

Oh, and I don't blame the CO for all the world's ills - just most of them!

 

[Moo]

You said "its not in very good condition and beyond restoration."

But is there absolutely no possibility of lifting the tiles & pamments and re-laying them? The pamments in our breakfast room were pretty manky, and had been covered in layers of assorted horrors, but our builder lifted the lot and relaid them (straight on the original soil, of course), with the best side up. They are much admired.

 

[thiambal]

I take your point about experts - but in this case he did seem to know his stuff. Sounded god anyway!

Sounded God eh! Cor, he must be good! :wink:

 

[tumbledown]

Moo, the pamments and the bricks have loads of cracks running through them. I'd be surprised if you would get any of the pamments up in one piece, and maybe 25% of the bricks. Also, the CO is very keen that the floor be left intact (although, "intact" may not be the best description of the floor). Taking into account the amount of usable material I could salvage, and the grief I would get for taking them up, it really isn't worth it.

 

[Moo]

A lot of my pamments were cracked, too. The lovely Steve took them up carefully and stacked them neatly so that he was able to put them down exactly as they had been (except for the ones he turned over). The cracks just add a bit more character.

 

[Nemesis]

It's starting to sound a fairly ancient and maybe significant floor, which possibly should simply be left undisturbed but covered for practical daily use, although I think I'd be inclined to learn to love it.

 

[Penners]

A lot of my pamments were cracked, too. The lovely Steve took them up...

Lovely, eh? Have you got anything you want to tell us, Moo?

 

[Moo]

Not on the open forum, Penners. There are rules, you know.....

 

[tumbledown]

I've talked it through with the CO. It really needs to be covered over for protection. The pamments have been dated as 17C, the brick part as a fair bit later. The isn't mich more than a third of the pamment side left and about 2thirds of the brick side. In the middle you can see the footings of an inglenook fireplace that was removed some time ago. the rest of the remaining area is just bare earth. So, its a little bit beyond just slinging a few rugs down. The plan is to put a layer for crushed chalk/sand down and lay a new pamment floor. Its difficult to describe, but you couldn't live with it as it is, and to repair it is not really practcal. Also, the CO is very keen that I do not disturb what is left. We may have had our differences, but I agree with her on this one.

 

[Penners]

Tumbledown - when it comes to getting your new pamments, I presume you know Bulmer Brick & Tile, near Sudbury?

 

[tumbledown]

Yes Penners - they are on my list of places to concider. The others that have been suggested to me are Norfolk Pamments and Cambridge Brick and Tile Co. I'm hoping to have a couple of days free very soon to call in on these places.

I'm still a little undecided if I should go with the UFH idea, and how well it will work in this situation, and how well it will go with the chalk base.
I've been told that I would struggle to heat the whole ground floor as well as most people would like, and not to rely on the UFH for more than 50% of the heating. The two main rooms downstairs are quite large so at least it may cut down from two radiators to one.

Also, i'm not really sure how much extra expense the system will bring - so, not sure if it is worth the effort or not.

 

[Penners]

Do let us know what you finally decide, and how you get on.

 

[tumbledown]

Does anyone have any ideas what to use for insulation under the UFH which will keep the floor breathable, but still protect/not damage the original brick floor benneth?

The chap I've talked to about helping me lay the floor says that in the past he has used hemp blocks, followed by chalk, followed by UFH pipes laid in sand, followed by bricks/pamments.

The only proplem with this is that he says the hemp blocks need to be about 5 inches in depth. The other layers would propaply add another 5 inches. Ten inches on top of the existing floor would raise the floor level too much, and of course digging down is not an option because of sole-plate positions/door ways etc. I can't really raise the floor level by more than 5 or 6 inches (which brings it back to the level of the old concrete floors).

So, any alternatives for hemp blocks that are breathable, efficient and a fair bit thinner?

 

[biffvernon]

LECA - light expanded clay aggregate - Womersleys sell it (as do others). Give Mark Womersley a ring and ask his advice - a mine of information. You could use the LECA as an alternative to the sand and make it whatever thickness you have space for.