For stress relief i would cut across the width of boards and not with the length.
Depth of relief cuts in wood flooring.
Cupping is when the board becomes curved across the width of the flooring.
The relief cut kept the flat surface of the casing and base off the wet wall surface and also provided a bit of air circulation behind the wood which helped prevent cupping and warping.
Position the circular saw in front of the newly created butt joint with the saw guard retracted the blade clear of the flooring and the weight of the saw balanced on the.
The differing rates between the two thicknesses will cause a log or board to slip.
This reduces the cost of shipping and makes the materials easier to handle.
This should be a series of grooves or fluted across the width not one large groove.
Stress relief depth should be from 20 30 of overall thickness stress relief along the width should be from 50 65 of the finished width dimension.
The stress relief prevents your hardwood flooring boards from cupping maintaining it s flatness.
For example if you re thinking about installing a wide plank hardwood floor in your home that means pretty much anything that s 5 inches wide or wider you may want to consider opting for rift and quarter sawn flooring.
Blade widths are usually 1 8 make sure that the cuts are evenly spaced either one cut creating two halves two cuts creating thirds three cuts creating quarters ect.
Relief cuts in flooring these small cuts out of the bottom of flooring actually have 2 purposes.
Plaster is pretty much the origin.
To help counter the differing degrees of shrinking and swelling among these layers of unlike materials the bottom layer gets kerf cut.
Deeper than the thickness of the flooring.
Freshly cut wood called green wood is well saturated with natural moisture from its sap and resins.
This would be done at 8 12 on center.
Knowing what cut your hardwood flooring is isn t just for aesthetic reasons it s mainly structural.
The relief cut helped the molding span over the plaster grounds and the slight high spot right at the back of a jamb.
Set the saw blade depth 1 16 in.
Firstly it breaks the tension that causes wood to cup.
Secondly it cuts the surface area that contacts the sub floor.
Similar to plywood engineered flooring is manufactured by sandwiching top and bottom layers of hardwood around interior core layers of lesser priced processed composites.
Kerf cuts are small grooves sawed into the underside your deck boards using a circular or table saw to relieve the surface tension.
As shown in the example below.