Recommendations on Fitting and Finishing

ABOUT OUR TIMBER FLOORING

All raw materials are graded and air dried at source
All our timbers have been kiln dried to have moisture content of between 7-10% (BS8201) All our timbers are machined twice for extra precision Our timber flooring has been machined to T & G, and in most cases, ends matched, which allows for easier installation and minimum wastage.

SITE CONDITIONS:

Site Conditions are extremely important and can make all the difference to a timber floor. The overall fabric (walls, floors, timber etc.) of the building should be thoroughly dried out so that there are no visible signs of moisture or condensation. All wet work (concrete, plastering etc.) must be completed and dry before you think of having the flooring delivered. Dehumidifying a newly built/extended environment is crucial. This can either be achieved by running the heating system for a prolonged period – with good ventilation or alternatively a dehumidifier can be used.

(a) All under floor concrete slabs should be dried to 2% moisture content and this may take at least 1 month per 25mm thickness of slab. Concrete sub floors must be clean, dry and flat (use a self-levelling compound to correct any errors, again ensuring that it is completely dry).

(b) Existing flooring, plywood, flooring grade chipboard or MDF sub floors should be in good structural condition, level and free from rot and fungus. New timber joists, battens and supporting timber should be kiln dried to 15% and under.

(c) Ambient conditions should be with in the ranges of Temperature of 15°c to 27° (BS8201) and relative humidity of 35% -65% (BS8201).

(d) Timber should be acclimatised in the room where it is to be laid at the conditions expected (BUT only if the conditions are right) for at least a week.

(e) Expansion gaps of 15mm should be left around the perimeter of the floor. For spans over 6m in width, 2mm washer gaps must be left at 1m intervals across the floor.

The effects of Heating and Climate on Stability

(a) As mentioned before the timber needs to acclimatise

(b) Expansion gaps are left around the perimeter of the floor.

(c) Seasonal variations and levels of heating may cause the timber to expand and contract. Small gaps may appear during winter when the heating is turned up, but these should close up again during the summer months. Timber kiln dried to 7-10% moisture content will react adversely to humidity levels below35% and above 65%, so for these extreme environments advice should be sought as to how suitable various products are.

(d) Areas exposed to excessive variation in heat and humidity are not suitable for a solid timber floor, in this environment an engineered floor is more suitable.

Under Floor Heating and Solid Hardwood Flooring

There are no hard and fast rules about the suitability of under floor heating system and timber flooring, it will depend on many factors, i.e. U value, room geometry, air circulation etc, plus the design of a suitable heating system. Speak to your heating supplier and ask for information on the suggested moisture content of the timber before it is laid. It may be worth thinking about laying a multi-layered floor, which has been cross-engineered for extra dimensional stability. This makes it ideal for going over Under Floor Heating. It is advised that these boards are adhered to the sub floor rather than floated.

Key points for wood floors over Under Floor Heating:

(a) Solid floors are not suitable.

(b) Heating systems need to be properly commissioned prior to the floor being fitted.
Commissioning should include slowly turning the heating up until it runs on the highest setting and then over a 7 day period turning the system off.

(c) You must install floor thermostats.

(d) Maximumrunning temperature at the screedmust not exceed 27°c.

(e) Floors fully bonded to the sub-floor will conduct heat better than floors floated over an underlay and will require a lower running temperature.

(f) Pre-sealsmustNOT be used on screeds over under floor heating.

(g) Rooms with poor U values will need greater levels of heat through the floor than well insulated rooms. You need to seek advice in this instance to check that a screed temperature of 27°c will provide enough heat in this instance to keep the room warm.

(h) Hot water systems create a smoother flow of heat than electric systems that are prone to hot spots.
(i) Do not lay rugs over wood over under floor heating, (if you know where a rug will be omit pipes from this area)

(j) Timbers with poor coefficients of expansion, like Beech and European Maple are not suitable for laying over under floor heating.