Installing Hardwood Flooring Over Concrete and Wood Sub Floors

Expansion & Contraction of Hardwood Flooringbut do not use solvent-based strippers under any
"The flooring shop said to leave 10mm for solid woodcircumstances. The use of residual solvents can
floor expansion at the walls...now the boards arecreate problems with the bonding of flooring
lifting off the floor." Ill informed advice like this oftenadhesives. It is important to ensure a proper bond
leads to floor problems. Many flooring sales peoplebetween the adhesives and concrete and wood
unfamiliar with solid wood flooring assume expansionpanels.
is the same as laminate flooring. In reality that 10mmIf you have a wooden subfloor you will need to lay a
is not enough for solid wood flooring.plywood base over the existing floor boards (we
What Is An Expansion Area? Why Do We Need It?recommend using 4mm -6mm exterior grade
Expansion areas are spaces left around the perimeterplywood and screw down every 15cm along the
of rooms, against fixed objects such as columns,edges and at 20cm intervals throughout the rest of
thresholds, hearths, skirting boards, and otherthe board using the 1 inch deck screws) before
stationary items built or secured into the framinginstallation, this will then give you a smooth and level
structure of the home. Even though Hardwoodsurface for you to install you hardwood flooring onto.
flooring used is no longer living and breathing it stillYou will need to leave a 15mm expansion gap around
reacts to moisture changes in the environment. Thethe perimeter of the room for large areas over 6
cells in the solid wood will take on or absorb moisturemeters in length we recommend 18mm expansion
when the relative humidity is high, or when exposedgap. To maintain this gap during installation spacers
to water. Expansion takes place, and the hardwoodare provided in the kits. After you have installed the
grows, for lack of a clearer term, across the grainhardwood floor you can cover this expansion gap
(width) of the plank (see below, not all will react thiswith scotia or new skirting boards The 15mm
way). Conversely when air moisture levels decrease,expansion gap also needs to be left in doorways
moisture content evaporates, shrinking of the solidwhere the hardwood floor follows through from one
wood will occur.room to another we sell on this website a full range
When we say spaces, they are defined as installingof door profiles available to match your floor.
the hardwood flooring up to and away from theNailed Down Installations
fixed objects. For example; "we recommend at leastNailed down installation is the traditional way to install
15mm small to medium area-18mm expansion onhardwood floors and can be done either directly onto
larger areas at the skirting board or wall if newwooden subfloor or on a concrete subfloor with the
skirting to be fitted."use of battens. When fixing battens onto concrete
Hardwood flooring can react to the presence ofyou will need a power-actuated nailer to drive
moisture. In the dry winter heating months, moisturethrough the battens and fix directly into the
can leave the wood flooring causing the floor toconcrete, firstly lay out polyethylene moisture sheet
contract slightly in size, which can leave slight gapsthen plywood over the battens to create a new sub
between each floor board. In the summer monthsfloor. We recommend 12mm exterior grade plywood
when the humidity is higher, the hardwood flooringand 2inch x 4inch battens. Lay battens around
will expand and the gaps will disappear. If there is tooperimeter at ½ inch from the wall, leave
much moisture in the subfloor it will cause the wood¼ inch gap at each end. Position the first
planks to cup, or buckle. Nearly all problems related tobatten so its centre is 16 inches from the outside
hardwood flooring are due to improper installation andedge of the perimeter batten. Lay out the remaining
sub floor preparation. This is why it is important whenbattens across the area 16 inch intervals. Always
installing hardwood flooring that you follow thecheck you battens are level using a level gauge you
correct recommended installation methods by themay need to use cedar shims to level out dips in the
manufacturer.concrete, slide the shims under the battens until level.
Direct Glue Installations(If in doubt we recommend consulting a professional
A direct glue installation requires the use of a flooringfitter for this method).
adhesive applied directly onto the subfloor (neverWooden Subfloor
directly apply to the boards). This method can beHardwood floors can be nailed into existing wooden
used on concrete and wooden subfloors. When donesubfloors such as floorboards or plywood but not into
correctly this is the most stable method for fittingchipboard floors as these are not strong enough to
solid wood flooring as the elastic flooring adhesivehold the nails. The floorboards must be in good
allows the floor to expand and contract with nocondition and level if not it is advisable to lay 6mm
problems.exterior grade plywood down first.
If you are laying over a concrete subfloor you willTo avoid creaking, check over the subfloor and
first need checked the concrete moisture, if the floorsecurely fasten any loose floorboards. For added
has a moisture content of over 4% then either waitsoundproofing it is also advisable to use a standard
until the sub floor dries to meet this level or use anfoam underlay.
appropriate moisture barrier, we recommend Sika MbWhen you nail down a solid wood floor you use a
Primer to ensure no damp rises up into your newPorta Nailer to drive a nail at a 30 degree angle
floor.through the tongue and into the subfloor. Porta
Also note that new concrete slabs require a minimumNailers can be hired from any good hire shop but are
of 60 days drying time before covering them with aexpensive to buy.
wood floor.Again you will need to leave a 15mm expansion gap
All Concrete sub-floors must be dry, smooth, levelaround the perimeter of the room. To maintain this
and free of structural defects. If the concrete subgap during installation spacers are provided in the
floor is uneven we recommend using sika latex selfinstallation kits.
leveling compound to level the subfloor. The concreteAfter you have installed the floor you can cover this
must also be free of contaminants i.e. paint, oil, waxexpansion gap with scotia or new skirting boards.The
grease, dirt and curing compounds (the reason for15mm expansion gap also needs to be left in
this is that you need the self leveling compound todoorways where the floor follows through from one
bond to the sub floor).These may be removedroom to another; we sell full range of door profiles
chemically or mechanically as your local hardwareavailable to match your floor on this website.
store and they will sell you the correct floor cleaner,