Old floors in period homes have their charms, but also their drawbacks, often presenting uneven, cold, and sometimes damp, surfaces underfoot. Frequently the problem stems from the surface the floor was originally laid on.
Insulating and levelling an old floor
Old materials were designed to be “breathable” and to absorb and evaporate moisture from the whole surface area. Damp floors can occur when a non-breathable material, such as a thick rug, is laid over the top, thereby preventing any moisture from evaporating, or when an unsuitable layer of insulation is positioned underneath.
To make old floors more comfortable for modern living, one solution is to take up the tiles, stone or parquet, and dig out the floor to a level that will allow for a damp-proof membrane, level concrete, insulation and the new floor covering.
The problem is that cement-based concrete and damp-proof membranes can be impervious to air and moisture, and this can cause damp beneath the floor, or in the walls.
There are methods for insulating under these floor coverings that won’t interfere with their ability to breathe. Options include a mixture of natural hydraulic lime binders (NHLs), or insulating aggregates. Both of these materials, unlike many modern impermeable systems, have the ability to absorb and emit moisture. They can also be installed successfully with underfloor heating.
- The floor will need to be dug up to the required depth before the ground is levelled and compacted.
- A layer of expanded clay beads is then laid followed by a breathable membrane and then a limecrete.
- This insulated layer is then covered in underfloor heating and a lime-based screed.
- The resulting breathable insulated floor can then be finished with the original flooring material, be it quarry tiles, stone flags or a breathable floor covering such as sisal or coir.
- Any polish, sealants or finishes must also be breathable.
- A cork-edge insulation can also be used around the perimeter of the walls to prevent “cold bridging” – a weak spot in the insulation.
Repairing wooden floors
Reviving old timber boards does not usually take long. Although there are many floor restoration specialists – who will charge around £20-£35 per square metre to complete the work – the project can be tackled by most confident DIYers and will involve fixing gaps, sorting out squeaks and scratches, and varnishing.
To do it yourself:
- First, scrape off any glue or adhesive on boards, punch any exposed nails down to below the surface using a nail punch, and remove staples.
- Nail down loose boards and replace any broken ones with those of the same finish.
- Fill gaps — large gaps can be filled using a thin strip of wood glued into position, while smaller gaps can be filled using papier-mâché covered in water-based wood dye to match the floor.
- Lastly, sand the floor. Sanders are available to hire, but check the grade of sandpaper you will need, which will depend on the state of the floor. Wearing goggles and a sand mask, sand with the grain for even floors, or diagonally at about 30-40 degrees for uneven, moving side to side.
- In the case of parquet flooring, if sections are badly damaged or loose, they can be taken up and replaced with new before the whole surface is varnished or sealed.
Cleaning and sealing tiles
Part of the beauty of these breathable tiles is that any moisture that comes up through them can simply evaporate into the air. Traditionally they were treated with boiled linseed oil to make them more resistant to stains. Over time, however, this wears off and they become porous once more.
- Sealing original tiles with a modern impervious sealant is not recommended – moisture will become trapped beneath and try to find another way out, often up the walls.
- Try breathable stains, such as Tile Doctor or some Lithofin products.
- If the tiles are badly stained or covered in adhesive or paint, clean them using a mixture of natural stone cleaner and water.
- Paint can be removed using Nitromors or a similar recommended paint stripper, but be sure to treat the tiles with boiled linseed oil afterwards.