Some queries from renovation novices

[Lisa H]

My husband & I have rather impulsively bought an old long house in co Mayo, in Ireland. It is in a spectacular setting, but doesn't have a water supply (although the stream running past it is tested for drinking quality & all the neighbours draw from it as well), no bathroom or kitchen & slightly problematic access - you have to ford a river twice to get to it....... We have now replaced the asbestos roof with slates & are turning our attention to the interior. There doesn't seem to be a noticeable problem with damp, but the chimneys have obviously had a considerable amount of rain down them and those walls are stained with a combination of rain water and peat soot. The walls are granite and the mortar is very crumbly. The lime (I assume?) plaster is very loose in some places but not in others, does it all need to be completely stripped back? If so, is there anything that can be used rather than a hammer & chisel as that is proving to be agonisingly slow? Also, should all the crumbly mortar be removed as well? The intention is to replaster the walls, but does the stone need to be sealed with anything?

We have also started to break up the concrete floors and have removed a huge amount of granite (we have probably reduced the level by 3 or 4 ") leaving behind rubble but are worried that by the time we have reconcreted, put down a damp course & insulation, underfloor heating etc, the floor level is going to be way too high. Should we take out all the rubble & dig out the earth before replacing the rubble etc, or should we just live with having low doorways (its OK for me as I'm only short!!)?

Any top tips gratefully received!!

 

[Gervase]

Crikey, sounds like you've got your hands full!

With the inside, I'd consolidate any stonework with new lime mortar, knock off any plaster that looks set to drop off and leave the rest, putting on new lime paster to match (one, two or - unlikely - three coats) and feathering the new to the old.

If the plaster is lime plaster then it should come off fairly easily with a hammere and bolster - it's the cement renders and gypsum plasters that are the sods to remove. As the wall is hard granite, an SDS hammer drill with a broad chisel bit could speed things up.

As for sealing the walls - you need to keep them breathable; that's how old buildings coexist with damp surroundings. The only thing you should be thinking of is limewash or a lime render (roughcast or 'harling' being the most appropriate for your place).

And for the floors, if you're going to have a concrete slab and membrane (which isn't always necessary - and breathable floors make for a better building in many cases, but that's another issue...) you'll need to dig right down at least eight inches, as the hardcore will have to be compacted before the blinding goes on, followed by the membrane, the slab, the UF heat pipes and the screed.

Your easiest bet is to find someone with a Bobcat or mini digger - you can get models that fit through doorways - and use that; it will save a lot of backbreaking work.

And if you can get hold of a copy of the excellent Stone Buildings by Patrick McAfee, published in Ireland by O'Brien Books do so - it will answer an awful lot of your questions and help banish a lot of worries.

 

[Penners]

Lisa - I shouldn't bother to wait for any more posts. You've got it all in one from Gervase!

 

[Lisa H]

Thanks Gervase! It is indeed going to take a lot of hard work to get it habitable, but it was a bargain......
Just so I am clear, we need to only remove the plaster that comes off easily as anything else can stay put, even if its soft enough to dig a screwdriver into?


The mini digger & motorised barrow are already booked for the end of the month when we are out there again.

Please can you explain a bit about breathable floors? Its fair to say that it is a very damp environment as not only do we have a river we also have inumerable streams running down off the mountain. Fortunately the house is on a dry hillock and doesn't seem to be damp even its mostly not had a back door, watertight windows etc

 

[Manny]

Sounds like a fantastic setting Lisa, I'd love to see some pictures

 

[Gervase]

A lot of perfectly good plaster will always be soft enough to dig a screwdriver into! If it's stuck fast on the walls, let it stay. The basic principle of restoration is to keep as much that's original as possible (and it's also cheaper).

Breathable floors are what all floors used to be until the philosophy of housebuilding changed from flexible and breathing structures to rigid and sealed structures.

The idea is that, by being breathable, water vapour transpires through the floor, rather than being displaced by a plastic membrane, forced to the edges and up your walls (which is what happens in older buildings that don't have damp-proof courses - and there is no way you'll get a DPC into a granite building, whatever the injection cowboys try to tell you!).

They're coming back into vogue again, as people realise the benefits of a breathable house. Using hardcore, expanded clay aggregate or glass, topped by a slab of hydraulic lime concrete, the modern breathable floor can comply with building regs and give you a sound base for underfloor heating.

Have a look at http://www.limecrete.org.uk/ for more details.

 

[Lisa H]

Manny would happily post pictures, but can't work out how to (am new to this forum!)

 

[Nemesis]

Have you a digital camera, with pics loaded on your computer somewhere?

 

[Lisa H]

Gervase am off to trawl round that site & see where it leads me to...... one of the postive benefits of having such diabolical access (1/2 mile of muddy track up a mountain, not forgetting the river crossings) is that we are unlikely to be inundated with people helpfully offering to come & do unnecessary jobs for us :lol: .....

 

[Lisa H]

Have you a digital camera, with pics loaded on your computer somewhere?

yes, have them loaded onto my PC ready to bore people with at a moment's notice

 

[Nemesis]

OK! A number of ways to post.

Try one. This is easy to start, assuming the file isn't too large. Others you can do but sites need to be registered for. (Photobucket is one).

Click below - Photogalaxy link.


Click on the link, click browse, it should find your pics (mine are in My Pictures...) find the pic, click on pic or link, and then click 'upload'. The pic will load to the site. You will get a new screen with the pic and a box full of incomprehensible rubbish.

Click on that and it should all go blue.

Then CUT that link - and PASTE it here into a post.

Try preview and hopefully...

You may have to play about a bit. There's an area on the site for testing but try it here in this thread and if it all goes pear shaped yell. You can always edit out later!


Click here:


http://host.photogalaxy.net/

 

[Moo]

Fortunately the house is on a dry hillock and doesn't seem to be damp even its mostly not had a back door, watertight windows etc

In which case, why would you want to go to all that trouble and expense putting in damp-proof membranes?
As someone said in another thread - if it ain't broke, don't fix it. It sounds as though there'll be lots of other opportunities to spend your hard-earned cash on this house!

 

[NT]

IMHO it would be a right bodge to lose height because you cant be bothered to dig the floor to the right level.

Re concrete vs limecrete floor, I would definitely go with concrete & dpm for this one. Youve got granite which is not permeable and thus does not absorb water and get damp. With your walls the only difference would be that a permeable floor would continually add evaporated water to the interior. Brick and granite walls behave quite differently in this respect.

With the plaster, I'd remove anything thats not stable, otherwise youre putting a lot of work in for a result that wont last. If its stable but not superhard, thats lime for you, but if its so soft its going to deteriorate in normal use, nows your time to replace such areas.


NT

 

[Lime]

IMHO it would be a right bodge to lose height because you cant be bothered to dig the floor to the right level.

Re concrete vs limecrete floor, I would definitely go with concrete & dpm for this one. Youve got granite which is not permeable and thus does not absorb water and get damp. With your walls the only difference would be that a permeable floor would continually add evaporated water to the interior. Brick and granite walls behave quite differently in this respect.

With the plaster, I'd remove anything thats not stable, otherwise youre putting a lot of work in for a result that wont last. If its stable but not superhard, thats lime for you, but if its so soft its going to deteriorate in normal use, nows your time to replace such areas.


NT

My feelings exactly.

 

[Nemesis]

Concrete is very ecologically not good. Limecrete is rather better.

 

[Gervase]

Concrete is very ecologically not good. Limecrete is rather better.

My sentiments exactly. Building accounts for a quarter of the CO2 production in the UK, and the use of lime rather than OPC would reduce that considerably.

And I wouod use a breathable floor even with igneous stone. Water moves through the mortar, and if the wall is double-skin rubble stone, the filler will almost certainly be a mixture of soil, lime waste and small stones, which will not be impermeable.
In my house the lower courses and foundation stones in one area were of dolorite - a very hard Preseli bluestone. A membrane and concrete floor had been laid by the previous owner, and damp and mould were evident on the inside walls to a height of about 18 inches. Moisture had wicked up through the mortar and reached the plaster (admittedly gypsum) where it was weeping through small cracks.

 

[Nemesis]

I always rather though that the breathability of brick and stone buildings relied more on the lime mortar than the building material but then I'm merely a woman so what could I know.

I agree however - lime, even if bagged hydraulic, is better than cement for most applications.

Our house had plastic floor covering laid on top of the flags. Walls were very wet, even though lime. It was wicking up trying to escape.