Rules for Builders in the Use of Insulation Board

By J. G. Brennen, Manager, Insulation Sdes, E. K. Vood Lumber Co., Los Angeles.

Ultimate success in the use of any product depends on how closely rules pertaining to its usage are followed. Indi'r'iduals or groupl of individuals who invent -or perfect a new product-or plocess learn through years of experimentation what can be done and what cannot be done with the product of their efforts. '

When a new product'is putron the marketl a set of rules formulated by its inventors or sponsors accompanies it. To follow thele rules generally means that the product will do what is claimed for it. To depart from the rules and apply those that may have been successful in the use of some other product, intended for a similar purpose, generally meanJ failure to get the maximum benefit from the product. I

While insulating board is not a new i,nvention, it is a comparatively recent one. Its inventors, and pioneers in the use of it, have learned by experience the best ways of using it. A resum6 of their discoveries are given here as a guide to others so that complaints that have come from those who have not followed the rules may be eradicated.

The first rule to be followed in the use of insulating board is to nail the panels lengthwise of studs, not crosswise. The panels should be centered on the studs and nailed as directed in instructions for use accompanying orders.

Panels should not be forced into place. Enough space should be left for expansion.

Studs should be true and properly spaced, and should be of dry stock. If green'stock is used it will warp and pull away from the panels. The studs and joists should be 16 inch centered. not 24 inch centered.

George Burnett To Visit East

Insulating boards are shipped from the mill bone dry. They are s[acked in piles in the same condition in which they emerge from the kiln and it takes considerable time for the panels to adjust themselves and take on the prevalent air moisture content.

In,rmany instances where complaints were received that the panels buckled between the studs, it has been found that new stock had been immediately nailed and exposed in bottr sides and had taken up the moisture conteirt very quickly and naturally this caused expansion.

It aso has been found that where new stock was used as a plaster base, that the rapid absorption of moisture from the plaster caused a violent expansion of the boards.

Of course, the dealer cannot carry in stock such materials until it has absorbed the prevalent moisture content, nor can the manufacturer anticipate what conditions will be in any certain territory and adjgst the moisture content of the boards to meet such a situation.

So it has been found good practice to wet down insulating b.oards just as kiln dried lath and shingles are wet down in lumber yards. This should be done twenty-four to thirtv-six hours before the boards are to be used and it will be found that the boards will expand to the maximum and when nailed in place will slowly contract. When used as a plaster base the boards will not contract until the plaster has set and then the slight readjustment will be taken care of by the resiliency of the board and with no danger of cracking the plaster.

Those who have followed the foregoing suggestions have met with universal success in the use of insulating boards and insulating lath.