Dreaded concrete floor

[Bayliss]

As an newbie my first question is one which has no doubt been addressed previously, however I am keen to read your thoughts and advise on the following problem.
My little timber framed cottage in Suffolk has suffered by the inclusion of an concrete floor in one of the rooms. I intend to break out this and replace it with old stock brick floor or pamments? Which compound (substrate) should I be using to lay bricks onto? I guess lime mortar for the pointing? Should I start brick laying at one edge and work across the room? And lastly, how should I finish the floor off, sealant seems to me wrong as I want the floor to breath? Thanks for any considerations.

 

[Penners]

To answer your questions one at a time (but as an amateur, not a professional):

1. I would lay the flooring bricks on sand.

2. You could point with lime mortar, although I've heard of a pointing medium called Geofix, which looks extremely easy to use, and claims to be water-permeable. But I have no personal experience of it. I wonder whether others have, and could comment? http://www.geo-fix.co.uk/productfeatures.html

3. The best method is start in the centre of the room. Set up two taut string-lines across the room at exactly 90 degrees to each other, and parallel with the walls, crossing in the centre of the room (if that geometry works - which it probably won't! But the 90 degrees is the most important thing.). Try to calculate the location of your string lines so that you're not left with cutting very thin slips of brick to fill in at the edges - decent half-bricks or similar or much easier to cut.

The room will then be divided into four quarters.

Now start to fill one quarter by laying your bricks accurately along the string lines. Once you've got these properly set, you can just fill in across the room.

 

[JoceAndChris]

Welcome to the forum Bayliss! If you think the bricks look a biy unfinished once laid there are all sorts of breathable products available. Womersleys will be able to advise, or you could just use linseed oil. (which will darken the colour).

 

[Bayliss]

Thank you for the good advise, now I just need an electric kango and away I go.

 

[Lime]

A couple of years ago I relaid a tile floor.
I used lime mortar as a base because the sub soil was prone to having a spring ant invasion.
However the point I mean to make is that I used a laser level to set the floor.
It made levelling so easy I wouldn't use anything else ever again.

 

[chuckey]

This would be a good time to put in a DPC, 2" of foam insulation then flooring grade T&G chipboard to provide a dampproof warm substrate for your new flooring materials. You could even lay in (into the surface of the foam) underfloor heating pipes thus future proofing your house with the posibility of solar or heat pump cheap heating.
Frank

 

[chuckey]

As for laying out the room, the most importent line is the one that hits you when you walk into the room or look through the door at the opposite wall (at the fire place perhaps?). If necessary do this by eye rather then measurement, but as Penners said put another line at right angles to it and try and visualise the effect. Pamments are normaly laid chess board style and are harder and smoother then bricks. For ease of laying and looks? , lay them diamond style it tends to disguise most laying out flaws (see concrete block driveways).
If you can get a batten say 6' long and as wide as your finished joint and little bits of the same material, lay your batten down on edge, splodge out your mortar, set the other joints with the little bits, remove battens and tamp down to your finished height, easier if you have set a few reference height blocks around the floor edge. If you are going to use ashlar joints - best of luck (tho' you do save on battens)
Frank

 

[Gareth Hughes]

This would be a good time to put in a DPC,
Frank

It would be an even better time not to, given the havoc they cause in old buildings.

 

[Schoolmarm]

This would be a good time to put in a DPC, 2" of foam insulation then flooring grade T&G chipboard to provide a dampproof warm substrate for your new flooring materials. You could even lay in (into the surface of the foam) underfloor heating pipes thus future proofing your house with the posibility of solar or heat pump cheap heating.
Frank

You are so persistent with this kind of advice. It isn't the right advice for a timber framed cottage, it isn't the right advice for the majority of queries on this forum.

Why do you continue with it?

 

[AMc]

As no one appears to have mentioned it...
Removing the floor may require Listed Building Consent - if you're listed, even though it's concrete - speak to your Conservation Officer

Removing the floor may require a building notice and/or building control approval. Renewing the thermal element (a.k.a. the floor) may require you to improve it's thermal performance (a.k.a. insulation) in which case you'll need to dig deeper and take into account vapour movement (a.k.a. breathability). Speak to the Building Control department at your local council to be sure.

Underfloor heating is lovely, don't fit the electric stuff as it's expensive and inefficient. You definitely need insulation to stop your heat going into the ground.

 

[Bayliss]

Thank you to all posters with invaluable advise, the only reason I want to remove the concrete floor is due to the damp being pushed to the walls surrounding this floor. Its not an listed cottage despite being around 250/300 years old. This surprised me when we went to purchase but I guess Suffolk has an abundance of ancient housing.

 

[MdB]

As AMc says, if you remove more than 25% of your floor area then you will have to fit insulation. To be breathable, this will have to be limecrete (I'm sure there are other insulating breathable floors but I don't know of them) made from leca which will require a depth of 400mm or so. This could cause your house structural issues so don't just start digging. If you go this route, I would strongly suggest fitting underfloor pipes as underfloor heating is lovely..

 

[Schoolmarm]

There could be a floor underneath already.

 

[mivec]

There could be a floor underneath already.

I was going to say the same.

We had the same problem but after a bit of investigating found the original brick floor underneath.
I say 'original' but we we're told the floor would have been originally been pammets (one row still exists) that were then replaced with bricks some point during it's 450 year history.
The concrete was a pain to remove but well worth the effort, other than a few rows of bricks missing the floor was intact.

It was amazing to see the moisture from the soaking bricks evaporate before your eyes each time a lump of concrete was removed.

 

[Schoolmarm]

That floor is beautiful.

 

[Jill]

Wow lucky you, what a find. We were left with just a small section in the corner of the room, i'll have to be happy with a couple of photos and the knowledge of what was possibly there many years ago.

 

[mivec]

Thanks.
I think we are lucky to have a cottage that was 'renovated' by lazy people in the 60's. They couldn't be bothered to remove anything, they just covered it up!
We recently discovered an original wattle and daub wall inside, what I though was, a modern stud wall.

I must say the 3rd photo was once the floor been finished, missing bricks replaced, repointed in places etc. It didn't look quite like that to start with.
It was covered in some sort of bitumen paint. Lots stuck to the concrete, most of the rest scraped off easily but some was a pain to remove. We left the worse of the stained bits rather than damage the bricks, after all, it's all part of it's history.

 

[AMc]

Thanks.
I think we are lucky to have a cottage that was 'renovated' by lazy people in the 60's. They couldn't be bothered to remove anything, they just covered it up!
We recently discovered an original wattle and daub wall inside, what I though was, a modern stud wall.

I must say the 3rd photo was once the floor been finished, missing bricks replaced, repointed in places etc. It didn't look quite like that to start with.
It was covered in some sort of bitumen paint. Lots stuck to the concrete, most of the rest scraped off easily but some was a pain to remove. We left the worse of the stained bits rather than damage the bricks, after all, it's all part of it's history.

Perverse as it may seem to us now lots of this work was done to deal with damp floors and unpleasant living conditions. At some point our old kitchen floor was covered in black gunk then screeded with cement. The room next door was also covered in a thick layer of concrete to cover a soil pipe laid across the floor when it was turned from a store into a bathroom. Thankfully being 'lazy' meant we had several hundred floor bricks to use in the kitchen we made by knocking these rooms together. I'd prefer a lazy moderniser who leaves the original stuff in place than the more thorough ones who who rip every window, door frame and cornice out .

 

[FamilyWiggs]

Bayliss,

I relaid a floor in our place a couple of years ago. They were handmade two-inch thick tiles, which I thought were called Heather Browns, but now understand these to be more regular than mine which all differed in size and thickness noticeably, and were much more granular in construction. I know they were handmade as they even have paw prints in some of them!

A few tips I picked up by trial and error:

Getting the visible line right as you enter the room is key. Rather than using string lines, I used a couple of lengths of batten and used this to ensure that the full length I was tiling (I did rows rather than quarters) was straight. With differently sized tiles, it is very easy to go off-straight very quickly. I spent a long time setting out each row dry, and selecting which tiles would go where. I would then lay the first and last tiles in the row, place the batten and then fill in the mortar and then lay the tiles between them using the batten to retain a straight edge. I used a long level to ensure that each area of the floor was broadly flat and level - but was not overly concerned about this as I wasn't intenting to play bowls on the floor once finished!

Unless you have exceptionally regular tiles, you will never stay square as you lay. I found that laying the tiles offset rather than chessboard was much more forgiving of the lines, and having a one cm point enabled me to even up the rows without it being too obvious. I found that 10mm foam insulation broken up into little pieces and slotted between the tiles whilst the screed set was a good way of retaining regularity in the points.

I laid onto a lime screed. When all were laid I then brushed the joints with a dry lime mortar mix and sprayed the floor. This seemed to work, although as it "sank" a little, I did end up doing some hand-pointing too.

I got through a couple of the 40 quid B&Q electric tile cutters (they really are carp) cutting the edge tiles. Because of the thickness of my tiles the cutter wouldn't cut all the way through. I had to remove the guard from the machine (which means water sprays all over you, so remember to reverse the machine and sit behind it and pull the tiles towards you and the water sprays away!). Score surface of the tiles deeply, flip over, put a bolster chisel in the groove and tap with a hammer.

I have sealed with a few coats of linseed oil and that is it. All told it probbaly took me a week to do a 15-foot square room. Here are a couple of "during" pics. I'll take an after today and you can see the final effect.

Hope this helps. I think I enjoyed this part almost more than any other aspect and am very proud of the floor and the effect it creates in the room.

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[Bayliss]

Thank you one and all so much for excellent tips and info', this is an great site.