We cut away wood sheathing
that interferes with the new porch, apply primer to the old
framing to deter rot, and install a new 2x6 ledger board.
Bruce W. Maki,
Modern deck framing often employs a ledger joist that is
attached to the exterior wall of the house. Perpendicular joists
connect to the ledger using metal joist hangers.
||After the old porch decking was removed, there
was a beaten and weathered layer of wood underneath.
|These grayed boards exposed at the corner are
part of the solid wood sheathing that covers the outside
walls of this old house. This sheathing is nailed directly to
the outside of the wall studs.
Some of these sheathing boards are almost 20 inches wide (i.e. a
1x20 plank). Try finding that kind of lumber today!
||In the corner, the lower part of the sheathing
was reasonably intact. But other parts were badly cracked. I
didn't want to install our porch ledger board over a weak and
uneven substrate, so I decided to cut away part of the
|Some of the nails in the sheathing were rather
rusted. This is a common occurrence in old houses.
||This is typical of the point where the old stone
foundation meets the wooden sill plate. Sill plates often rot
because they are in contact with masonry, which can absorb water
and dampen the wood, which will rot whenever the moisture
content is above 29%.
The loose rocks will allow cold air to enter the house in
the winter, and these gaps also let bugs gain entrance to
I believe that this house has experienced no sill rotting
problems because the foundation extends about 2 feet above the soil.
This makes it difficult for water to wick upwards into the wood.
Also, since the house has a basement which receives some heat from
the furnace, the lowest parts of the framing are not exposed to damp
crawl-space air. It's benefits like these that make me a firm
believer in full-depth basements.
|Once I had calculated the exact level of the
ledger joist, I snapped a chalk line and ripped the sheathing
board with a circular saw.
||Since I could not cut all the way to the end, I
used a reciprocating saw to cut the last few inches (red arrow).
|I applied a coating of oil-based primer to the
exposed sill and rim joists. Why? Because it can't hurt and
Primer will deter moisture from soaking into the
wood, if some water ever gets behind the ledger joist.
||This inexpensive drill bit is good for drilling
counter-sunk pilot holes.
||I used 3" Deck-Mate screws to install the ledger
joist to the house. With the pre-drilled and counter-sunk holes,
the screw heads were easily buried below the surface of the
|The installed ledger boards, which were 2x6
pressure treated pine.
Note: One thing I omitted in
this task was a metal flashing strip to keep water from getting
behind the ledger joist. Many new-home builders employ such flashing
strips (often called a Z-flashing because of its shape), but I was
not able to pry the siding away from the house to insert the upper
leg of the flashing.
We plan on replacing the siding on most of this house (with
original wood siding), and at that time we will install an
Warning About Deck
I have read numerous accounts lately (2004) about serious
injuries and deaths caused by collapsing decks. In
most of these cases the culprit was an improperly installed
deck ledger which pulled away from the house when the deck
was loaded with a crowd of people.
Some of these ledger boards were simply nailed to the side
of the building with common (smooth-shank) nails, which
offer very little resistance to pull-out forces. Deck
screws are definitely better than common nails at resisting
pull-out, but deck screws may still not be enough.
Current building codes specify the number and size of
fasteners used to attach a ledger board to a building. I
have seen some hefty requirements, such as 2 rows of
½" lag screws spaced at most 16 inches apart. Your actual
requirements will depend on your conditions, so contact your
local building department or construction codes office
for exact information.
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- Cordless Drill/Driver
- Circular Saw
- Reciprocating Saw
- Basic Carpentry Tools
- Treated Lumber, 2x6
- Deck Screws