Proper lumber storage pays off

I-'ROPER lumber storage will proFvide you with a dimensionally stable product as well as help maintain a bright, clean appearance for your lumber.

Correct storage provides for proper inventory turns, giving you economic use of your stock. Also, lumber that can be easily loaded or unloaded saves time and labor costs.

But, approaching winter weather, with alternating periods of wet and dry, can seriously degrade yarded lumber. Common characteristics resulting from the continuous wetting and drying of lumber in storage include warp, twist, cup, crook, splits, and possible staining. These weathered effects can be minimized through proper yard storage.

Most yards use some combination of three principal types of storage: open yard; closed, unheated shed; and closed. heated shed. Lumber should olways be stacked on stringers off the floor or ground. This will keep it out of any standing water and allow air to circulate around the stack.

Dry dimension lumber that comes from the mill with paper wrappings should be stored with the wrapping in place with any tears repaired with tape. Even with outdoor storage, Western Wood Products Association found that the average moisture content of paper wrapped bundles did not change more than 2%90 throughout any given l2-month period. Tests were conducted in the Pacific Northwest. where the bundles were subjected to heavy and constant rainfall.

Use of plastic or canvas tarps should be limited to short periods of time. They do not provide the same type of protection as paper wrapping. Since plastic coverings do not breathe, they capture and hold moisture rising from ground level.

Unwrapped green lumber stored outdoors can be degraded by rapid drying as well as excessive moisture. When green lumber drys too rapidly it is susceptible to splits, checks and warps. During warm weather, green lumber should be "stickered" for prolonged yard storage.

Green lumber is likelv to deterior- ate if stored in solid piles outdoors for any extended time. The first signs of deterioration are stain and mold. with decay setting in later. Because moisture gravitates towards the center of the pile, the worst decay will occur in the centerwhere it is usually not visible from the exterior. This is commonly known as pile burn.

If pile burn begins, the lumber must be "stickered" and allowed to dry. This will kill the mold and arrest the , decay. It will, however, leave you with some unsightly lumber. Although the lumber may retain its strength and serviceability, it may be very difficult to sell to your customer.

Besides open yard storage, some type of protected outdoor storage is usually necessary in all lumber yards.

An open shed will provide direct protection from sunlight and rain. It allows the same atmospheric conditions and equilibrium moisture content as the prevailing climate. In hot, humid areas it may be the'most desirable type of storage. But you should remember that one-inch boards dried to an 890 moisture content, and stacked outdoors under a roof in solid piles will gain about l9o in moisture content per month in hot, humid weather. However, inside a closed, unheated shed, the gain in moisture content will be about .390 per month in the same weather conditions.

The closed, unheated shed is probably the most popular type of storage for welldried and high-quality lumber items. Dry lumber, finished materials and siding should be protected from the elements. As an extra bonus, the closed, unheated shed is

Story at a Glance

Proper lumber storage saves time & money...protection from weather, stock rotation, correct delivery techniques add to value...storage infor' mation available.

useful in preventing the regaining of excessive moisture in dried materials. Dry lumber can be solid stacked, either flat or upright.

Another type of protected storage is the closed, heated shed. In this type of storage, the equilibrium moisture content of lumber can be controlled by circulating heated air. This may be necessary in certain climatic regions or for certain specific types of product storage.

One key to proper lumber storage is stock rotation. Newer stock should be kept in the yard since it will usually store better. The first. or oldest stock in your yard, should be shipped out first to the customer. This inventory method is called "fifo" for "first infirst out."

This brings up another storage point directly affecting your relationship with builder customers: jobsite delivery and storage. Lumber with a stable moisture content delivered to the jobsite can help keep usage defects, such as nail popping, or baseboard pullaway to a minimum. These types of builder problems usually find their way home to the lumber yard.

An effort should be made to deliver the lumber in the order it will be needed by the builder, particularly when the unloading is to be by the "rolloff" method from the truck. This is especially important when a forklift is not available on the job site.

The top of the stack should be mud seal stock, then floor joist material. Other stacks would be subflooring, wall plate stock, precut headers, cripples, studs, and so forth in the order they would be needed.

This, of course, saves the labor it would require for the builder to restack the material to get at an item buried in the load.

If polyfilm is being used to protect Iumber after delivery, put a layer on the ground to keep moisture from rising into the lumber. Stack ends should be left open, so air passes freely through the stack of lumber.

Weather protective coatings, such as "cherry toning" or "Milbrite," are good for a short time period only. They last about three months from the time of application at the mill. Do not expect them to protect dry framing lumber left on the job site during the rainy season.

Dry exterior siding and finish material should be stored in a closed unheated area off the ground. Never store finish materials or dry siding over "green" concrete. If this is the only place available, polyfilm should first be placed over the concrete before the materials.

Interior millwork should be stored in a closed dry area. It should not be delivered to the job site until the con- tractor is ready for its use. It should not be placed into a house until the gypsum board joint work has been allowed to dry.

Getting the most out of the lumber stock you purchase depends a lot on how you store it. More information is available from the U.S. Forest Service in a booklet you can obtain from the Forest Products Laboratory in Madison, Wi. The Western Wood Products Association also has a Spec Point OG-5) on Lumber Storage. Write to Western Wood Products Association, 1500 Yeon Bldg., Portland, Or. 97204.

G00D TECHNI0UES for lumber storaoe include

(1) proper stacking to facilitate stoc-k rotation and lOading and unloading with forklift of the open storage which is common at most yards.

(2) Aligned bunks and banded courses mainlain dimensi0nal stability. (3) 0pen shed design provides forklift access as well as protected storage against inclemenl weather.

(4) Closed, unheated shed allows lumber to maintain climatic balance without excessive moisture gain. Dry lumber can be solid stacked, either flat or upright. (5) Adjustable racks accommodate various dimensions of lumber. 0pen air design permits air flow around and through stacks while covered top restricts sun and rain (6) High quality moulding and lrnisfrng materials stored in uprighl stacks maintain equilibrium moisture content in a closed, heated shed.