Recondition a Wood Floor

From DIYWiki

Reconditioned timber floors can be a real asset to the beauty of a building. Old wooden floors can get into a sorry state over time, but most are fairly straightforward to recondition, even when they look beyond hope.

Decisions first

Perfectionism

DIYers often attempt to achieve a perfect finish, and too often cause themselves problems and sometimes damage their floors in the process. The reality is that floors with many imperfections can look very good once done, and perfection is by no means required. The standards required of timber floors really are very different to those of general joinery. For some reason the eye is happy with all sorts of defects that would never be tolerated in a door frame or piece of furniture. The fact that floors are normally viewed from over 5 feet away also conceals various minor imperfections.

Character

There are basically 2 approaches to restoring old floors. One is to repair and recondition them, keeping many of their various foibles and patina, and resulting character. The other approach is to flatten them, eliminate gaps, remove all trace of patina and end up with a floor that looks more like modern laminate. The latter is sometimes chosen without realising the options, and the character of the result can often disappoint. With awareness of the options you can choose what you want.


Core steps

5 steps are needed to recondition an old floor:

Thorough clean

A thorough clean is the first step. There are various ways to do this.

Mopping

Mop repeatedly with biological washing powder and a tiny amount of bleach. The mop is wrung well so all standing water is avoided. The basic method is to mop the floor briefly, leave it a few minutes, mop again, and keep repeating for an hour or two. There's no need to work the mop hard, the water and powder does the work and the surface merely needs rewetting.

Soaking timber is rarely recommended, but the wood is not wetted long enough for damage to occur. The final mopping is done with clean water and the floor soon dries. Such treatment would ruin wood if done regularly, but a one off soak is harmless.

  • Easy
  • no cost
  • materials to hand already
  • very effective on unwaxed floors
  • not effective on waxed floors
  • removes all patina, leaving softwood almost white (this gradually recolours)

Wire wool & solvents

Wire wool, elbow grease and a mixture of turps, meths and

  • Slower work
  • Leaves the wood oiled
  • Much less patina loss

Caustic soda

Caustic soda is a paint & grease remover that is sometimes harshly criticised for its effects on wood. It's better avoided.


Removal of coatings

Sanding, scraping and paint strippers may be used to remove any paint or the infamous black gloop.

Paint strippers

Caustic soda paint stripper is best avoided due to its deleterious effects on wood.

Methylene chloride based strippers are toxic and volatile, and require high levels of ventilation. This makes them ill suited to large area stripping indoors.

Sanders

Opinions vary as to which type of sander is best. Use of a hand held sander just to remove surface paint is not nearly as drastic as the results of a large flat floor sander. However it does remove patina.

Rotary sanders (drill + flexible backing pad) are disliked by most DIYers, as correct handling technique is necessary to avoid gouging, and the technique is not too easy to learn. On the other hand if it is learnt, these provide quick progress. If you've not mastered the art, practising on some scrap is strongly recommended first, and you may well decide the tool is not for you.

A 40 grit fibre sanding disc cut to fit a rubber backing pad works well. Conventional sand papers are not able to cope with the forces involved. The coarse grit is used to remove muck, then the job is finished with a finer grade to give a smooth finish.

Other tools

Scrapers may be metal bladed or wire wool.

Woodworking chisels may also be used for small spots if dragged backward acoss the wood rather than pushed forward. This is quick on paint spots.

Rotary wire brushes are not recommended. Although effective, sufficient force to remove paint results in significant surface damage.

Paint stripping rotary wheels are available. 2 common types are flap sanders and grit on a flexible plastic scouring wheel.


Repair of damaged boards

Damaged face

Boards with a damaged face can often be turned over. Colour matching may not be great, but applying identical finishes reduces this, and the colourations tend to equalise over time. Sometimes the surface is rough sawn and needs sanding, and sometimes it's mucky and needs a clean.

Split boards

Split boards can have crosspieces screwed to the underside to repair and reinforce them. (Just glueing the split is not usually sufficient.) Metal makes a stronger fix than small bits of wood. Long strips of wood running along the plank may also be used for greater strength, obviously taking care to avoid adding bulk where the supporting joists are encountered. Often the damage at the crack is then not noticeable from a standing position, even if it's easily seen up close.

A little matching filler can hide greater damage. If a board has broken up badly at the crack, as is liable to happen with very thin boards, replacement is the obvious option. Sometimes though it's possible to turn the board round so the damaged part is at the other end out of sight. This avoids mismatching wood, so looks better if the damage won't be noticed in its new location.


Refixing where needed

Loose floorboards

Loose floorboards may be fixed down with

  • lost head nails
    • will probably lift up as the last ones did
  • ring shanked nails
    • better pull resistance
    • but larger heads
  • Secret nailing
    • for T&G only
  • Screws
    • ultimate pullout resistance
    • but generally large heads
    • Heads can be reduced by turning (lathe), but this is labour intensive. Only workable for a few screws.

Loose parquet blocks

Parquet was commonly fitted using hot bitumen. Very few things stick to bitumen, and re-use of hot bitumen is an effective option which avoids any need to clean the blocks off. Bitumen in solvent is much easier to lay, and usable for small areas that can be protected from foot traffic for a week or 2. Styccobond F21 is a specialist glue designed to stick to bitumen. Manufactured by Ball, and used at a rate of around a litre per square metre.

Full refit

Where T&G boards are being relaid to eliminate gaps, they may be secret nailed to give a nailhead free finish. A nail gun designed for this makes the job far quicker. Original nail holes may be filled if wished. Note that secret nailing makes later lifting problematic.

The other fixing methods in the above list can also be used.

Board ends should rest on a joist. Where this is impractical, a cross nogging can be fitted under the board ends.

Where all boards are being replaced, fitting used boards of the same or similar size gives a historic characterful appearance, whereas new timber looks more like laminate with its dead flat & white appearance.


Finishing

Bare wood is relatively difficult to clean properly, so timber floors are usually coated to improve appearnce and make life easier.

Varnish

A non-slip varnish intended for floors can reduce accident risk.

Wax

Wax is easy to apply, and gives a nice soft sheen, but needs regular buffing and repplication (it traps dirt over time).

Tinted varnish

This is best avoided. Varnish chips in time on floors, and the appearance of white chips on a tinted floor is especially bad.

Stain

Where the appearance of mellowed wood is wanted at once, it may be tempting to resort to stain. There are downsides to this, and softwoods will gradually recolour themselves if not stained.

  • Stains tend not to absorb evenly into pine, and the result can be patchy and look quite poor.
  • Staining also sometimes results in very unnatural colouration, causing further problems.
  • Usually it's better to use a cleaning method that avoids removing the patina in the first place.
  • Stain makes the wood darker in the long term, not generally desirable with pine.

More

Sanding

The sanding of domestic floors has become popular as a result of people copying practices formerly only used for commercial premises, meeting halls, etc. However sanding the whole floor down is not usually appropriate for domestic floors.

First it's almost never needed. Domestic floors that are so worn as to become unsafe are rare, and where they do exist they are usually centuries old, and a strong piece of character that should not be removed. This is in contrast to commercial premises, public halls and so on, where heavy use results in enough wear to make resurfacing necessary.

Second, such practice writes off a percentage of floors by exposing worm eaten cores. Once the worm eaten core is exposed, the floor is very unsightly and unsalvageable. Historic woodworm infestation is common in old houses, and is normally harmless, despite the worries often expressed about it. Burrowing of flooring plank cores is no rare thing, and does not normally cause a problem as long as the floor is not sanded.

Third, since it's not needed, it's an unnecessary use of money, time and work.

4th it removes all trace of the patina and character of the floor. The resulting character of sanded and unsanded floors are quite different. Unsanded reconditioned floors look like old floors in superb condition, whereas sanded ones look more like flat new laminate floors, and too often look out of place in an old building.

5th heavy sanding weakens the floor, which in a minority of cases can be a real problem, though usually is not.


Gaps

Old floorboards usually have a lot of gaps. There are 3 options:

1. Accept the gaps as part of the character of the floor. A no work option, which makes this popular.

2. Use filler in the gaps. Homemade filler can be cheap and accept stains, but bits can fall out over time, as wood does flex a little in use.

3. Re-lay the whole floor. This is the only way to properly eliminate the issue, but is a lot of additional work. Bear in mind that

  • some boards can break on lifting
  • breakage can be very high if boards are in poor condition, and this is not always obvious before lifting
  • all pipe profiles etc will need to be recut,
  • additional matching wood will be needed as the boards are relaid more closely


Replacement Timber

Floorboards

When a few boards are to be replaced, new wood is best avoided, as it looks so out of character with its square edges, flat face and white colour. Used boards fit in much better and can be bought from dealers of used building materials and salvage yards.

Replacement boards that are thinner can be packed where they sit on joists to bring them level.

Where all boards are being replaced, fitting used boards of the same or similar size gives a historic characterful appearance, whereas new timber looks more like laminate with its dead flat & white appearance.

Parquet

The same principles apply to parquet. But parquet brings an additional option, to include non-matching blocks laid out to form an artistic pattern, typically either in the centre or around the edge of the room.

To suit an old house stylistically, a few points should be borne in mind:

  • The standard of block finish should match the existing blocks. New blocks with dead flat faces would look clearly modern and out of place.
  • Patterns of a period style are much more likely to work with an old building
  • Avoid the common mistake of selecting a scheme with a grandeur out of all proportion to the property.

The contrasting blocks may be a different colour or shape, or both.

Following these simple guildeines greatly increases the likelihood that the end result will look right.


Listed building caveat

Your conservation officer should be consulted before any restoration of boards in a listed building. Presenting them with the details of the planned work can reduce delays.


See Also