Outdoor Decks and Patios:

Few home improvements can match a wood deck for usefulness, beauty and enhanced value to a home. For adults, patio decks offer outdoor living space for entertaining, sun bathing and dining. For children, they provide an excellent outdoor play area. But the best news about a deck is that it is an ideal home improvement construction project for the average handyman or woman.

Deck Table 1: Minimum Beam Sizes

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Table 2: Minimum Post sizes

	
		Load Area (sq. ft)=
Height		beam spacing x post spacing
(ft)		48	72	96	120	144	
up to 6		4x4	4x4	6x6	6x6	6x6
up to 8		6x6	6x6	6x6	6x6	6x6
Vertical loads figured as concentric along axis.		
No Lateral loads considered

Deck Table 3: Recommended Spans for spaced deck boards

		
		Spans in Inches
		Laid Flat				Laid on Edge
5/4x4	5/4x6		2x4	2x6			2x4
16	16/24**		16	16/24**			48
**Although 24 inches is a safe span, undesirable 		
deflection or springiness may occur.

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Deck Table 4: Maximum allowable spans for deck joists

Joist size	Joist	spacing
(inches)	16	24				
2x6		9'-9"	7'-11"
2x8		12'-10"	10'-6"
2x10		16'-5"	13'-4"

Deck Table 5: Railings


Distance	Post 		Cap
between		size		size
posts		(inches)	(inches)			
2' to 3'		2x4		2x4
3' to 4'		2x4, 	4x4	2x4, 	2x6
4' to 6'		2x6, 	4x4	2x6
Side rails can be nominal 1" or 2" lumber of varying widths

Tables are based on lumber with 1200 psi bearing stress
rating and a live load of 40 psf.
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