Make it the full width of the porch or slightly wider depending on your porch design.
Attach an awning ledger board to a wood siding house.
So make a mark above 7 to 8 inches and keep a minimum gap of 2 inches at one of the ends.
Determine how high it must be to provide an adequate slope to the roof.
Anchor deck joists to the ledger with joist hangers filling each hole with galvanized joist hanger nails rated for pressure treated wood.
Attach 2x6 rafters to the house with joist hangers and or supported by the ledger board.
If necessary use a sliding bevel to determine angles needed where the rafters will meet the ledger board.
Most house framing relies on building elements floors walls roofs being stacked one atop another.
Aluminum and vinyl siding can easily be removed with tin snips from an area one foot surrounding the ledger board location.
If you have beveled horizontal siding then use an inverted piece of siding as shown in the illustration here to create a plumb flat surface for attaching the ledger.
If your siding is not beveled you can simply screw the ledger tightly to it.
Also you need to keep enough open space approximately 3 4 inches above the top of the mounting bracket and ledger board.
Locate a position for a header or ledger board.
Attaching a deck ledger securely is only half the work of installing a ledger.
The screws should penetrate the ledger the sheathing the house and go into a framing beam such as a floor joist or a wall stud.
This is the only way to ensure the connection is water tight.
Predrill and sink 1 2 in.
Dia galvanized or stainless steel lag screws in every other joist space alternating up and down positions to keep the ledger from splitting.
In order to install the ledger board you usually need to remove the house s siding.
Rafters are placed on 24 centers and attached to the beams and settle joists are attached as needed image 1.
Never install a ledger board over the top of siding no matter what you hear this can weaken the connection.
A ledger relies on the fasteners and strength of the wood ledger board and rim board of the house to carry the deck live and dead loads.