herein 1 4 inch deep which is one third of the total thickness of the panel 10 the cavities have a diameter of approximately 11 64 inch with these characteristics the panel has good structural characteristics the panel may also be formed by using recycled paper products whereby to reduce the cost of the product and to provide a use for such paper such a panel also has a thermal insulating factor of r2 the cavities 13 are also disposed in parallel rows and offset from one another so that the perforations 13 of adjacent rows are disposed intermediate the perforations in rows on each side thereof referring now more particularly to fig2 there will be described the method of constructing the panel 10 of the present invention firstly wood products preferably but not exclusively aspen wood pieces 15 are fed to a wood pulp refiner 16 as is well known in the art to refine or pulverize the wood pieces into wood pulp the wood pulp is then transferred into a holding tank 17 into which hot water is fed from a hot water reservoir 18 this wood pulp is retained in the holding tank for a predetermined period of time herein 15 minutes so that the wood fibers expand to improve the sound absorption properties of the fibers recycled paper starch and wax is then added to the holding tank and maintained therein to form a composite pulp mixture the retention time is approximately 45 minutes a mixture or kneader apparatus not shown is provided inside the tank to mix the wood pulp with the paper starch and wax for ease of illustration the paper starch.