Stone Flags - Pros and Cons

[masochists-r-us]

Hi,
We have a very old stone built 3 cell cross passage house. The middle cell downstairs would have been the Hall or main room and most probably had stone flags on the floor. Nowadays, it has a concrete floor after being 'modernised' in the '60s which led to wet rot developing on all the timber skirtings over the years. The house doesn't have a big damp problem as such, but we want to do all we can to allow it to breathe. We are planning to break up and remove the offending concrete and have some lovely old flags to lay down, but before we do a couple of questions:
1.What should we lay them on - underneath the concrete is earth ?
2.Whilst committed to doing the 'right thing' (please feel free to comment we're not experts) I'm concerned about comfort and practicality of stone flags.Are they more comfortable and practical than they look ? (please don't suggest UFH - can't afford it, too complicated). Part of me would like a nice wooden floor.
3.What should we finish them with as they're rather grey and dusty looking ? I have heard wax mentioned, but there seems to be an array of 'stone sealants' out there. We would prefer something traditional if possible.
Thanks in advance.

 

[Moo]

We inherited old stone flags (between 2 and 3 inches thick) in our hall, and pamments in our breakfast room. All are laid straight on to earth and I doubt very much whether they've ever been sealed - we discovered them hidden under sedimentary layers of cement screed, red tile paint, lino, plastic underfelt and carpet.
The flags must have been worn smooth by a few centuries of foot traffic, because they have a dull but pleasant gleam (much envied by a neighbour whose hall flags were sealed and varnished at some time). The pamments don't gleam. Some bricks, used to fill in the gap between flags and wall in a narrow passage, had that dusty look until we gave them a dose of Danish Oil left over from doing the kitchen worktops.

I tend to walk around indoors in bare feet quite a bit and have never found either surface uncomfortably cold.

 

[Penners]

stone flags ...are they more comfortable and practical than they look ? Part of me would like a nice wooden floor.

My personal view is no - they're not more comfortable than they look. I would always opt for a wood floor, out of preference. Stone is harder and colder.

But practical? Well, it depends on what sort of practicality you're after. Stone flags are probably more "fit-and-forget" than wood, and they're generally more durable. However, as you're laying a new floor, durability in either material is only likely to be of concern to your great-grandchildren!

But stone is not a great deal more resistant to staining than wood. Both stone and wood can be stained by a variety of things. The degree of vulnerability to this will depend on the type of stone and the efficacy of the finish.

But for all that, a flagstone floor is very beautiful, and I could live very happily with one.

If you do lay flags, you could bed them on a dry-mix of sand and lime, supported/levelled with five-point dobs of lime mortar.

 

[Roger H]

Run your UFH pipes under the stone and plumb them in when you can afford it? Could in future be plumbed into woodburner, solar thermal etc...Pipes and 'eggbox' system not that expensive....

 

[MdB]

UFH needs a good layer of insulation underneath it - 100mm of Celotex or 250mm? of insulated limecrete or similar. The pipes also need a screed on top of around 70mm. With flags on top and something solid underneath you are talking 300mm to 400mm of depth which is a lot of digging out and may well undermine the walls.

It is not complicated to fit though and it is great when you switch it on and start feeling the warmth .

 

[Lime]

If you do decide to lay flags a modern laser level will save endless hours of work, always assuming you want it/ need it/ can have it level.

 

[chuckey]

Flags look nice but are not a practical floor surface, however if you want them, and can't afford UFH, then as a compromise, which I did was going from the top down, flags, 22mm T&G chipboard, 50mm foam, DPM, 6" concrete, which is mainly to increase the bearing area for the walls as they don't have foundations.
Frank

 

[Penners]

going from the top down, flags, 22mm T&G chipboard, 50mm foam

Sounds like a recipe for bouncy flags to me. Don't you get problems with grout cracking?

 

[Lime]

There's nothing wrong with laying flags directly upon earth but it is a skilled job and takes time.
To level the earth and allow it time to settle is important.
If you can, avoid disturbing the earth when taking up the old floor.
Alternatively, and the choice I would make, is to use the method Penners suggests.
I also agree with him concerning the comfort of stone.
Very nice to look at but can be hard on the feet like all hard flooring.
The problem with laying a wooden floor is that takes away the opportunity for the subsoil to breath as there needs to be some form of membrane between the wood and earth.
If the floor is suspended ventilation is required.

 

[Pford75]

Electric UFH is much cheaper to fit...but more expensive to run. However, you can opt for the version which just takes the chill off the floor, rather than attempting to heat the room.

We have both flags and pamments similar to Moo....we have 8 & 6 year olds and a 2 year old who quite happily crawled around on both without any difficulty.

 

[chuckey]

The flags have been down for about 18 months and there is no sign of the grout cracking yet. The flags are very heavy (4" thick) so standing on one doesn't even double its loading. As the vertical joints are only there to keep the flags apart, fill them to within 1/2" of the surface with pea gravel/sharp sand and just finish the top off. To lift a flag then requires only to break up the top surface of the pointing and you can vacuum the loose filling out.
Frank

 

[Moo]

6" concrete, which is mainly to increase the bearing area for the walls as they don't have foundations.

How did the walls cope before they had the support of the concrete?

 

[Lime]

6" concrete, which is mainly to increase the bearing area for the walls as they don't have foundations.

How did the walls cope before they had the support of the concrete?

Yes I don't understand the purpose either.

 

[yamin]

Flags here - uncovered when we acquired the house. From the late 18th century, rather scruffy but come up beautifully with boiled linseed. Our 5 yr old twins run over them barefoot no complaints, various friends babies crawl on them happily, and old, incontinent dog hasn't stained them (no matter how hard she tries, bless her), but they have been very tolerant of 'that' kind of soiling!!!!! We now use the room they are in as a main living room (has logburner) - we cannot yet afford a rug so just flags, and although I personally wouldn't walk on them barefoot (I wouldn't walk ANYWHERE downstairs in this house barefoot, lets face it!!!!), they do not make the room feel cold. They certainly add character! I know they are laid direct onto earth.

 

[chuckey]

How did my foundations cope, quite well, but not 100% as the house is slowly falling down the hill. This being the favoured failure mode of the houses and barns round here. I have re-pointed the crack that runs between the roof via two windows openings to the ground, we'll see how long it lasts before it opens up.
Frank

 

[Penners]

old, incontinent dog hasn't stained them

The degree to which anything will stain a stone floor depends on two main factors. Firstly, the type of stone - some varieties are much more absorbent than others. Secondly, the extent to which the stone has been sealed, or saturated with decades of wax, oil, etc.

Of course, different substances stain to a different degree. Stuff like red wine, blackcurrant juice etc. can be very staining if they soak in. Acidic liquids can be very bad for limestone... and so on.

 

[yamin]

Well, if we're going to quote my old incontinent dog, she may as well star in a picture, together with a bit of the flagstone floor!!!!

 

[Penners]

Well at least the dear old thing looks as though she has the most comfortable bed in the house.

Which is as it should be.

 

[ljn]

I have a similar situation.
I wanted to do insulated limecrete with undefloor heating, but the concrete floor that covers half the basement is HARD and variable thickness. Budget is an issue. Also ceiling height.
The CO seemed fine about the idea "just be careful of the wall footings".
The builder said he'd need power tools to dig out the concrete, that cost and time would be apparent only when the job was well under way. A lot of rubble to skip.
The limecrete was a considerable cost but the main issue was the curing time.

The main deterrent was that I don't like the idea of a pneumatic drill and all the vibrations on a very old house.

Not sure what I'll end up doing...

 

[Carrie]

I'm interested in this thread as we're thinking of laying flagstones. I've yet to explore under the various levels of concrete in the hall and kitchen but am pretty sure there's nothing interesting. Trouble is sourcing old stones which don't cost a fortune or new ones that won't stand out like a sore thumb in this old house. Still have to sort out the levels first, which gives me time to consider what to do.