I'm sorry to hear about your situation, nothing is more frustrating than to have a brother treat our customers shoddily and have no respect for our most valued resource.
I've worked with the brazilian mahoganies & redwoods quite a bit, but you need to treat the redwoods (which are called mahogany by most) differently they have a tendency to cup if not finished properly and in a conscientious manner. Other species of mahogany such as ipe (and I've listed a few others below) are a little less forgiving.
4” wide decking should be installed with a 3/16” space between boards, while 6” wide boards will need 1/4'” space between the boards. This space will allow for air circulation, allow room for expansion and provide for the proper spacing as boards become fully seasoned. Approximate shrinkage and/or swelling is 3/16” on 4” decking and ¼” on 6” decking.
You need to get those deck boards up and spaced before you loose that investment. You don't want to go through a winter with those installed like that.
In order to help prevent surface checking, cupping and discoloration, it is recommended all Kiln Dried Hardwood decking be finished on all four sides, prior to or immediately after installation. Especially in dry, sunny conditions, finishing should be done prior to exposure to weather. Finishing Kiln Dried Hardwood on the underside of your deck will reduce potential cupping by inhibiting moisture from absorbing into the wood.
If a natural silver color is desired, finishing can be done with a water seal product such as Seasonite from Flood. Apply as soon as possible during or after installation of the deck. For best results, apply the treatment according to the manufacturer’s directions.
To maintain the reddish-brown color, a high quality penetrating oil finish with UV inhibitors should be used. Two coats should be applied during installation. Reapply as necessary to maintain desired look.
The natural density and alkaline content of Kiln Dried Hardwoods can cause a reaction with certain finishes affecting their drying and adhesion. A color change may occur. A test on some sample pieces is suggested to insure desired results. Kiln Dried Hardwood decking can also be pressure washed, but you must be careful not to damage the surface fibers by setting the pressure too high. Pressure washing may be necessary between oil treatments in order to remove surface discoloration.
The fir railing should have a solid stain. The railing cap should be either the Mahogany (brazilian redwood, ipe, Cumaru, Tigerwood, Cambara, Massaranduba, Angelim Pedra, Angelim, Angelim do Para, Angelim dos amarelos, Angelim pedra, Caramate, Ere joeroe, Erejoeroe, Lialiadon koleroe, Lialiandan koleroe, Para angelim, Para-angelim, Saandoe, Sapupira amarell, Sapupira amarella, St. Martin jaune) or a composite. They really take a beating.
Have a professional look at the fasteners on the decking and at the pressure treated framing as well.
Alter Eagle Construction & Design
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