In the home

Flooring

• Benefits
• Timber flooring specifications
• Main species of solid wood flooring
• Softwood flooring
• Main types of finishes
• Laying a solid wood floor on joists
• Tips on fixing hardwood
• Maintaining wood flooring
• Plywood decorative floors
• Fixing plywood onto joists
• Laying plywood onto continuously supported floors
• Underfloor heating

Benefits

A wood floor adds value - few features make such a difference to the appeal of a home.

A wood floor is an investment - a solid wood floor will last a lifetime and more, paying for itself time and time again.

A wood floor is individual - there is a wide range of solid wood floors available, from excellent value pine and spruce, through traditional beech and oak to exotic hardwoods.

A wood floor is easy to install - today's wood flooring is simple to fit, whether direct to joists or 'floating'.

A wood floor is easy to repair - dents and scratches can be readily repaired.

A wood floor is versatile - different looks can be created by stains, paint, stencils or a variety of different oils and lacquers. You want to change the look? Just sand down and start again.

A wood floor is easy to maintain - maintenance depends on the type of wood, the type of finish and the pattern of usage. After some years, the floor may be sanded down and re-finished to look as good as new (many, many times).

A wood floor is healthy - easy to keep clean and free of dustmites, wood floors are particularly beneficial for allergy-sufferers. Wood's humidity-regulating properties make a home healthier to live in, too.

Remember

Only use wood that has been kiln-dried to 8-10% moisture for flooring. For best results, allow the wood to stabilise to the room's conditions for 24hrs (48hrs for hardwood) before fixing.

Timber flooring specifications

Solid soft or hardwood floors come in a variety of

·  Lengths: 1200-5700mm

·  Widths: 70-250mm

·  Thicknesses: 13-30mm

Thinner boards are suitable for laying over existing floors, reducing the need to adjust doors and skirting heights. Boards from 18mm are suitable for fixing direct to joists. Individual production methods lead to minor dimensional variations, but the main finished sizes are listed below.

Main species of solid wood flooring

Softwood

1. Natural pine (redwood)
   Classic Scandinavian-style flooring. Good value, medium wear.
2. (Pre)-lacquered pine
   Easy-lay, easy-care.
3. Oak stained pine (lacquered)
   A more traditional look from a pine floor.
4. Natural spruce (whitewood)
   Simple, good value, medium wear.
5. Stained spruce
   An inexpensive way to get a colourful look.
6. White oiled larch
   A high quality flooring, with few knots. Suitable for heavy traffic areas.
7. Cherry oiled larch
   A warm, traditional quality look.

Hardwood

1. American oak (lacquered)
   Highly durable. A popular choice for all domestic floors.
2. American oak (oiled)
   Provides a stylish hardwearing floor.
3. European oak (oiled)
   Makes a design feature of the distinctive oak grain.
4. Maple
   A high quality hardwearing floor capable of heavy duty wear.
5. (Pre)-lacquered beech
   A hard, wear resistant floor, for a wide variety of situations.
6. American white ash
   A luxury hard wearing floor.
7. Chestnut
   Hard wearing floor with lots of character.

Softwood flooring

The main advantage of pine flooring is that it provides similar benefits to hardwood flooring at a substantially lower price.
It is also highly versatile, lending itself to a variety of finishes as suitable for a contemporary city loft as for a traditional country cottage and is widely used throughout homes in Scandinavia and mainland Europe.

Softwood flooring is naturally more vulnerable to sharp objects (although dents and scratches can generally be repaired and, being a solid material, some surface marking can become part of the character of the floor). However, new compression processes can provide pine flooring with greater hardness even than oak.

As with any wood floor, the amount of expected traffic and tracking-in of grit etc. needs to be considered when specifying finishes.

Use only specialised pine flooring. This comes:

• Shrink-wrapped in protected packs, complete with fitting instructions
• Kiln-dried down to 8-10%
• Tongued/grooved on all four sides
• Made from slow-growth timber (typically from Scandinavia)
• Taken from the heartwood at the centre of the log, for maximum stability
• Stress-grooved on the reverse

Standard spruce floorings, as found in general house building, are not suitable for exposed finish floors because of their poor decorative finish and because they are not specially kiln dried. This can cause shrinkage and gaps between the boards.

Main types of finishes

The choice of finish depends on personal preference but also on practical considerations.

Pre-finished lacquer

Suitable for all usages.

Advantages:

• Simple to lay, as no finishing is required
• Simple to maintain; clean with a damp cloth
• Hard-wearing surface protects wood

Disadvantages:

• No opportunity for a decorative finish
• Will eventually wear where traffic is heaviest; just sand down and re-finish

Lacquer/varnish

Suitable for all usages.

Advantages:

• Multi-coat application can provide highly durable waterproof surface, even across joints (a well laid tongued & grooved floor will have minimal gaps)
• Flooring can be given a decorative finish by using a coloured varnish or by staining prior to varnishing
• Hard-wearing surface protects wood
• Simple to maintain; clean with a damp cloth

Disadvantages:

• Applying the lacquer takes a little time
• Will eventually wear where traffic is heaviest; just sand down and re-finish. The use of a 'sacrificial' emulsion polish will enhance the protective qualities of the varnish (i.e. it will wear, instead of the varnish)

Oil

Suitable for areas exposed to relatively low traffic and grit, like bedrooms. Use one of many wood flooring maintenance oils available.

Advantages:

• Provides a natural finish which allows the texture of the wood
  to be appreciated
• Can be combined with stains for a variety of effects
• Localised damage, like dents and scratches, can be readily
  repaired with a fresh application
• Floor can be re-treated without sanding

Disadvantages:

• As the oil doesn't provide the impermeable surface of a lacquer,
  the wood will be more vulnerable to standing water or tracked grit
• Requires several initial treatments
• Requires regular re-treatment, typically annually, depending on
  wear and frequency of cleaning

Soap

Suitable for areas exposed to relatively low traffic and grit, like bedrooms. Use one of many wood flooring natural soaps available.

Advantages:

• Traditional treatment creates a deep lustre which gets richer
  over time and with repeated application
• Localised damage, like dents and scratches, can be readily
  repaired with a fresh application
• Floor can be re-treated without sanding

Disadvantages:

• As the soap doesn't provide the impermeable surface of a
  lacquer, the wood will be more vulnerable to standing
  water or tracked grit
• Requires several initial treatments
• Requires regular re-treatment, typically annually, depending
  on wear and frequency of cleaning

Lye

This is a treatment used to help preserve the wood's natural pigment and prevent darkening. It also opens the wood's pores prior to finishing. 

Stains

You can stain the floor before finishing with varnish, oil or soap.
n.b. as a varnish is not compatible with oil or soap, do not attempt to use the two together.

Paint

Wood floors can be painted in the usual way. A gloss finish will be easiest to keep clean.

Laying a solid wood floor on joists

• For best results, use a fixing clamp similar to the one shown, available from any builders' merchant
• Apply the same perimeter and expansion gaps as when laying a floor on joists
• A floor wider than 5 metres should be split into sections, with a 'T' piece, or threshold plate, fitted between sections to allow the floor natural movement
• Ensure the entire floor surface is clean, dry and free of projections
• Use a 1000 gauge polythene sheet, to form a suitable vapour barrier
• Additional thermal or acoustic insulation can be achieved through using recommended underlays (such as Hoebeek's, or 'Woodlay' from Swiftwood)
• The boards will need to be glued
• Turn the board wrong side up and hold it diagonally towards you
• Glue the upper edge of the tongue - when the board is turned the right way up the glue will run down the boards
• Apply the glue lengthways and widthways
• Remove any excess glue from the surface of the board

Tips on fixing hardwood

The right tools

• A hardwood floor is a significant investment; it always pays to use the best quality tools, underlay, finishes and adhesives
• Where possible, lay the floor last, to avoid damage

Nailing

• Always use nails (unlike softwood floors)
• Nail at 200-250mm centres
• Cleats may be used to allow movement in the floor
• Nail size can be reduced to 45mm (assuming an 18mm or thicker floor) if a 50mm cleat cannot be used
• Always use a recognised nailing tool, such as a 'Powernailer' with mallet and 50mm cleats

Fixing denser species

• To avoid splitting the tongues, vary the 45º angle of the nails
• It might also be necessary to drill pilot holes to make nailing easier; blunting nail/cleat ends will further help avoid splitting

Fixing to existing boards

• Ensure existing boards are dry
• Lay a plywood subfloor of a minimum 12mm thickness
• Lay and nail as onto joists

Finishing

• Wear a dust mask when sanding floors; eye protection may be useful to help avoid dust allergies sometimes associated with imported hardwood species
• Check with both wood and finish suppliers that the treatment is suitable - natural oils and chemicals of some imported hardwoods can react differently to certain finishing products
• If you are working with a new species, use a sample and test it with the proposed finish to view the effect

Remember

For best results, allow hardwood flooring to stabilise to the room's conditions for 48hrs before fixing.

Maintaining wood flooring

Basic advice

• Prevent the tracking-in of grit etc. by using effective entrance matting
• Avoid contact with sharp objects or concentrated pressure, like stiletto heels
• Place pads or cups under furniture
• Dry clean (with a brush, mop or vacuum) and damp clean (with a soap solution) regularly

Damp cleaning

• Use a flat mop with a natural soap solution, wrung damp to avoid excess wetting and to dry quickly. This removes minor stains and helps repair scratches and dents as the wood fibres absorb the solution

Persistent stains

• Sand the area lightly with grade 80 paper
• Re-sand smooth with grade 220
• Apply natural soap or oil and leave to dry

Oil or soaped floors

• Use a proprietary intensive wood flooring cleaner
• Scrub the floor with a mop soaked in the solution
• Remove excess dirty water with a mop wrung out in clean water
• Leave to dry naturally (for about 30-40 minutes)
• To re-oil, apply maintenance oil with a soft cloth and burnish
• To re-soap, use natural soap diluted with warm water

Machine maintenance (commercial premises)

• Remove all dry dirt
• Apply a solution of intensive wood cleaner with a rotary polishing machine
• Remove excess solution and dirt with a wet pick-up vacuum
• Treat with a light coat of soap or maintenance oil
• Remove excess soap or oil with a clean cloth
• When dry, floor may be burnished using a high speed rotary polisher

Plywood decorative floors

Specialist plywoods, such as Schauman Birchfloor (see later for stockists), provide attractive, structural and hardwearing flooring for both commercial and domestic applications. They can be laid onto a variety of surfaces, like joists or concrete, provided correct procedures are followed.

It is worth considering the following points at the design stage

• Are there any structural load needs?
• What is the nature of the sub-floor onto which the panels are
  to be laid?
• How will the floor be used?
• What wear resistance is required?
• What are the overall site conditions?

Schauman Birchfloor, used in appropriate thicknesses, laid to standard practice as a suspended floor, will meet the loading requirements of BS 6399 part 1:1984 "Code of Practice for dead and imposed loads" for domestic floors with a spanning range of 300mm-600mm.

More information on plywood can be found in the Builder's Guide to Plywood, available free from wood for good.

Specifications
The boards are made up of 1.4mm birch veneers (exterior glued, bonding class 3 BS EN 314:1993).

Protection
These panels have highly decorative faces and accurately machined tongued and grooved edges for easy fitting, so make sure they are protected from damage before use:

• Ideally, lay the floor last
• Treat the boards with a suitably thick coating of protective varnish/lacquer, like Dulux Diamond Glaze, before laying, to prevent damage (varnish is best applied thinly - build the thickness up by applying several layers)
• Seal the reverse face too, so as to ensure the boards stay in a balanced condition; check they are dry before laying.

Warning

If you use plywood structurally that isn't listed in code BS 5268-2:2002, you risk liability, should failure occur. Don't take the risk - all Nordic structural plywood is listed in the code.

Fixing plywood onto joists

Plywood panels are fixed in much the same way as solid
timber flooring:

• Ensure joists are dry and even, presenting a level surface (regularise, if necessary)
• Lay panels with the face grain parallel to the span
• Support all short edges on a joist
• Stagger end joints
• Support perimeter on continuous noggins
• Allow a perimeter expansion gap of 2mm/metre floor width/length, with a minimum 10mm gap
• Use a waterproof PVA adhesive to glue joints and panels to joists
• Secret nail/screw to existing joists, using galvanised annular ring shank nails 2.5 times the panels' thickness, or countersunk screws recessed 2mm below the panels' surface
• Space fixings not less than 10mm from the panels' edge and at 300mm intervals elsewhere
• For extra fixing, use a suitable mastic, applied to the underside of the panels and to the joists.

Laying plywood onto continuously supported floors

• Ensure surface is clean, dry and flat, free of any projections; screeded floors must be fully dry
• On concrete, beam and block floors, lay a 1000 gauge polythene sheet as a vapour barrier
• Lap and seal joints with a vapour-resistant tape
• Depending on the amount of thermal insulation required, an insulating underlay (such as closed cell extruded polystyrene) can be placed on the sub-floor
• Lay the panels with the short edges staggered
• Spot-bond the underside of the panels to the sub-floor with a mastic-type adhesive
• Allow expansion gaps as with fitting to joists
• Pre-plan access traps and provide support with noggins etc. on all sides.

Underfloor heating

Underfloor heating is actually very good for wooden floors because it maintains a constant even temperature over the surface of the floor eliminating hot spots close to radiators, but it's worth taking care to avoid problems with shrinkage.

Follow these simple rules:

1. Consult the manufacturer for specific advice about ranges suitable for underfloor heating
2. Follow the manufacturer's fitting instructions
3. Choose flooring with a maximum 8% moisture content
4. Do not store flooring in a cool or damp environment before laying
5. Unwrap and lay flooring loosely for a minimum of 48 hours in the room with the heating on (longer for hardwood floors)
6. Ensure your underfloor heating runs at a gentle heat. Do not run it hot.
7. Consider choosing engineered wood floors, which are made with an ultra stable substrate.