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CHIMNEY INSPECTION DIAGNOSIS REPAIR
COLUMNS & POSTS, DEFECTS
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DECK & PORCH CONSTRUCTION
DEFINITIONS of MOBILE HOME, DOUBLEWIDE, MODULAR, PANELIZED CONSTRUCTION
DEFINITIONS of ENGINEERED WOOD OSB LVL etc
DISASTER BUILDING INSPECTION & REPAIR
EARTHQUAKE DAMAGED FOUNDATIONS
FIRE DAMAGE vs MOLD DAMAGE
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FOOTING & FOUNDATION DRAINS
FOUNDATION CRACKS & DAMAGE GUIDE
FRAMING DAMAGE, INSPECTION, REPAIR
GRADING, DRAINAGE & SITE WORK
HOUSE PARTS, DEFINITIONS
INSECT INFESTATION / DAMAGE
KIT HOMES, Aladdin, Sears, Wards, Others
LOG HOME GUIDE
MOBILE HOMES, DOUBLEWIDES, TRAILERS
MODULAR HOME CONSTRUCTION
MOISTURE CONTROL in BUILDINGS
PORCH CONSTRUCTION & SCREENING
PRE-CUT & KIT HOMES
RETAINING WALL DESIGNS, TYPES, DAMAGE
ROT, FUNGUS, INSECT DAMAGE
SINKHOLES, WARNING SIGNS
STAIRS, RAILINGS, LANDINGS, RAMPS
STRAW BALE CONSTRUCTION
STRESS SKIN INSULATED PANELS
STRUCTURAL WOOD ASSESSMENT
TIMBER FRAMING, ROT
TRUSSES, Floor & Roof
WATER ENTRY in BUILDINGS
WOOD STRUCTURE ASSESSMENT
How much to space deck floor boards: this article explains proper gap size to leave between deck boards for drainage and drying, and extra steps to take to protect deck joists from rot.
We include a description of tightly-butted tongue-and-groove pressure treated deck boards as well as typical 5/4" thick pressure treated deck boards that should be spaced for drainage..
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When Lon Church constructed this outdoor stage for the Summerblue Arts Camp (Two Harbors MN), we knew that the structure would have to endure severe winters and strong summer sun without the protection of a roof. And because the surface is used as a performing stage, we used 5/4 tongue and groove treated wood for the surface - no gaps for drainage.
Sloping a solid deck floor to achieve drainage
To compensate for the drainage worry, we made sure to slope the stage (from back towards the front or audience side) - and the stage pitch became a theatrical feature.
Here is a photo of the stage in use [image file], courtesy Lon Church, Summerblue Arts Program.
Steps that were taken to avoid ice lensing and post movement for this structure are described at Ice Lenses, Frost Heaves vs. Frozen Soil Pressure.
Use gaps between deck boards to achieve drainage
But most decks need and can achieve spacing between the deck boards for drainage.
As discussed in Best Practices Guide to Residential Construction:
Watch out: don't leave wider gaps between still-wet treated lumber deck or porch boards during construction or you may find that as the wood dries, excessive deck board gaps can form a trip hazard, especially for people wearing high heeled shoes.
Protecting the Deck or Porch Joists from Leaves, Rot
This can be achieved by laying strips of felt paper or self-adhesive membrane (one approved for UV exposure) over the tops of each joist prior to laying the decking boards.
Photo (left) courtesy of Mark Morsching, Everflashing, shows an Everflashing stainless-steel flashing product installed over the deck ledger. Additional metal flashing is in use to protect the deck joist top from rot. Additional details about deck flashing and more deck flashing images are at Deck Flashing at Building.
To avoid deck joist top rot Morshing applies peel-and-stick flashing membrane material to joists and ledgers during deck construction.
Another proprietary product for this application, Vycor Deck Protector™, is available from Grace Construction Products. Membranes such as Vycor Deck Protector can also be used as a barrier between pressure-treated joists and joist hangers, flashings, or other metal hardware to reduce corrosion.
-- Adapted with permission from Best Practices Guide to Residential Construction.
This article series discuss best porch & deck construction practices, including choice of framing materials, decking or flooring choices & installation, how to select and use deck and porch structural and flooring fasteners, actual deck & porch framing construction details & connections, deck joist & beam span tables, how to build leak-proof rooftop decks, construction of covered & screened porches, deck & porch railing construction & materials, choices of finishes and stains for decks & porches, and past & current deck lumber preservative treatments with related health & environmental concerns.
Continue reading at DECK FLOOR LAYOUT or select a topic from the More Reading links shown below.
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