If you are considering a wood floor for your home or business, you should really read this article. This comprehensive, impartial, wood floor installation advice comes from our experts, who have been working with this beautiful and complex natural material for decades.

Everyone knows that wood floors come from a living, breathing object…. a tree, right? Most of us understand that a tree takes water from the soil it is growing in via its’ roots and distributes that moisture, laden with nutrients up the trunk along the branches and into its’ leaves where excess moisture is expelled into the air (transpiration). Most probably don’t know that this transpiration causes suction which brings more water up from the roots and that the conduit for the water through the trunk is made up of small straw like tubes known as xylem.

Even fewer will realise that in order for the roots to thrive and grow they also need to be nourished and for that to happen the sugars that are created by photosynthesis need to travel from the leaves, back down the tree to the roots and this is done via cells called phloem.

So now you know a bit more about the two basic components of a tree that allow it to live, of course just like us trees are made up than more than just a vascular system, they also need to have a skin like protective layer (bark), they don’t need a bone structure to support them but they do have heartwood which is the dead wood in the centre of the tree made up of previous years’ growth.

So now is the time to start telling you why all this is very important to you if you have a wooden floor because if I go into any more detail you will stop reading and you really need to understand this!

In the UK we have no real understanding of wood and so we put down beautiful wooden floors because we “like the natural look” and yet we expect them to behave like plastics or other materials that have never lived. In addition to this, the number of fully trained wood floor fitters in this country is woeful. A friend of mine runs a fantastic flooring school that is full of people wanting to learn about vinyl fitting and carpet fitting, but he cannot get people on his wood floor course!), yet it requires more skill, knowledge and equipment to correctly fit a hardwood floor than either of these man-made products. In addition, a badly fitted wooden floor can damage the structure of your house EASILY, that doesn’t happen with carpet or vinyl!

So if you are thinking of fitting a wooden floor here’s what you need to think about.

Wood Floor Installation Advice – Moisture Content

wood floor moisture metreWhen a plank is cut from a tree it is made up of heartwood and sapwood the former being old dryer and dead and the latter being softer, moister and vascular (our friends Xy and Flo). In order for it to be stable enough to be machined for its’ final purpose that plank will be seasoned over a reasonable period in the open air.

Immediately prior to machining, the plank will be stored inside to bring its’ moisture content down further. The extent of this will depend on the type of wood and its final purpose.

For flooring, it is not unusual for the moisture content to be as low as 7% when it leaves the factory but because the process has been carried out slowly and methodically the wood has retained its integrity and is flat and stable.

The scenario

So jump forward now to Fred the floor fitter opening the new packs of freshly delivered wooden flooring. They arrived early this morning (the driver loaded the night before) and Fred can’t wait to get fitting – well why not? It’s only wood, what can possibly go wrong? After all, the room has just been re-screeded and plastered and the heating isn’t on yet so it will all be fine, just like the carpets are. Fred has been fitting carpets for 20 years without a problem and the vinyl he’s done for the last couple of months with (barely) an issue, he’s a skilled floor fitter!

Wood floor Installation advice – Finding a qualified installer

So let’s talk about what should happen to correctly install a wood floor. It starts at quotation stage and in the above scenario, the process will go on for at least three weeks before floor laying is commenced.

  • At quotation the fitter or salesman should advise you of the suitability of the product you are considering for the environment it is being fitted in. They should further advise you about the pros and cons of your choice and what you should expect in terms of living with the floor.
  • He/she should inform you of the requirements that are necessary for a successful installation. This will mean measuring moisture, temperature and humidity levels in the subfloor and the air and stating that he/she will not fit the floor until the specified parameters are met. If your fitter does not have quality measuring equipment (Tramex or Protimeter for example) then do not proceed with them.
  • If the conditions are not correct at quotation stage (if a room has been recently plastered, screeded or heating has been off for a long period) then measurements will need to be taken at regular intervals and a record of the progress kept.
  • Once conditions are correct the wood should be delivered, stacked correctly and acclimatised in the room it is being fitted WITH THE CONDITIONS AS CLOSE TO LIVING CONDITIONS AS POSSIBLE.
  • Measurements should be taken again immediately prior to installation and this time should include the wood itself.
  • Installation should be carried out with reference to the manufacturers’ instructions.
  • On completion of the installation, the client should be given instruction on how to clean and maintain their wood floor and how to keep the conditions in their house correct for their floor.

So why did I bore you with the details of tree structure and what bearing does the above have on that?

The Scenario – What’s next

So Fred fits his floor, he hasn’t done any measuring so he doesn’t know that that the subfloor moisture reading is too high because the screed hasn’t fully dried, or that the plaster is still damp so the moisture in the air is too high. The wood itself left the factory at 7% but it was loaded last night and left on a truck outside so Lord knows what the reading in that is! He hasn’t done any training so is oblivious to the need for expansion gaps, the correct spacing around pipes etc., and he’s a geezer so he’s not going to read the instructions is he? Thank God the heating hasn’t been commissioned yet so he won’t be sweating buckets!

Wood Floor Installation Advice – Why Moisture Matters

moisture damae - wood floorSo what’s going to happen here? In all likelihood, the fact that the wood was loaded the night before is not going to be a big factor (unless it was not covered and it poured down rain) and in any case if it was slightly wetter than 7% it would help with the scenario that is developing.

The biggest issue is the moisture in the subfloor and the walls which once the heating is finally switched on are going to cause a massive spike in humidity in the room. The moisture in the air is going to get into the wood and travel along all those little tubes causing it to swell, not a problem for one piece of wood, after all, what’s one or two millimetres on a 75mm stave? Oh hang on, that’s 40 -80mm in a small room and Fred didn’t leave ANY expansion gaps, let alone enough to cover this.

In this scenario, if you are lucky the floor will just pop up, it probably won’t be economically recoverable so you’ll only lose a £1000 worth of materials (it’s a VERY small room), plus the labour (it won’t be Freds’ problem after all, will it?)

Worst Case Scenario

Of course, if you are unlucky (and yes I have seen it) you’ll push the wall down and lose all the wood (in this case it definitely won’t be salvageable), so substantially more than £1000 will be lost!

I have only scraped the surface of why you should only use a wood floor fitter who knows what he is doing. An environment that is too dry will result in a gap filled floor, a wood with lots of minerals in the heartwood can cause finishing problems, underfloor heating requires special treatment, all these issues can be correctly dealt with by the correct fitter and finisher, but without a desire to learn about wood specifically and equip themselves correctly your wood floor fitter is unlikely to be up to the job and you’ll end up paying the price.

It’s enough to drive you to an (a)xlem (sorry).

For more information on floor installation training follow this link.


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