Build a Timber Pergola
timber pergola can make a big difference to the appearance
of your property.
The instructions in this guide are for fixing a pergola
to an existing house. For a free standing pergola these
plans will have to be modified.
Step 1: Getting Started
First determine where you want to locate your pergola
against your house. Try and select as level an area as
possible - it will make installation much easier.
Take into account where trees and gardens are now or will
be placed, prevailing wind direction, summer and winter
sun to determine the best position.
(Click for a bigger image)
Step 2: Setting out
When you have decided where the pergola should be
positioned pencil mark the position of the ends of the
ledger beam on the wall. With a carpenter's level, plumb
these markers to ground level. Now use the same detail for
setting out (as our project guide for decking) to locate
the posts, position the beams and rafters etc. Details are
shown for fixing posts to an existing concrete patio and
also into a new footing - if this is a pad type footing it
should be no less than 300x300x300mm for each post. If
Contractors a timber deck with pergola over it, it is usual
to use common support posts for both structures -
100x100mm posts are ideal. All radiata timber must be
adequately treated - refer to framing sizes span table at
bottom of page.
Step 3: Fixing
Fixing ledger beam to house: If the wall is brick, use
masonry anchors at 1200mm apart. For a timber or cement
sheet clad house, the ledger beam should be fixed to every
Rafter overhang should not exceed 25% of the allowable
span, eg; rafter span of 2.4m = overhang of 600mm.
Pergolas with lightweight roofs should have the reafters
spaced at 600mm centres.
Deep rafters may require mid span blocking to prevent
See below for details.
Step 4: Staining/Painting
Make sure the stain/paint you choose is compatible with
the timber treatment and galvanised fittings. Follow the
manufacturer's instructions. Sawn timber is best for a
stain finish and dressed or gauged timber is preferable
for paint finishes. Alternatively, you may decide to apply
no finishing and leave timber to age naturally.
Step 5: Fixing Lightweight
This material should be fixed according to the
manufacturers instructions. Because of the open design of
a pergola, these materials will be subjected to
substantial lifting forces in high winds and the maximum
number of fastenings, screws or clips should be used.
The pergola design must allow for the slope of this
covering to permit rain water to run off.
Step 6: Bracing
Pergolas which are fixed to an existing house may not
require post bracing unless the width and length make
bracing on the corner posts necessary for support.
Step 7: Customise your
We have suggested sun control battens across the top of
the rafters - use this technique in selected areas.
Trellis panels will provide a privacy screen and wind
Seating and shelving designed around the posts will look
great. Hanging baskets full of flowering plants or
climbing vines in tubs will look great as well.
Hello Direct, Inc.
Spa Finder, Inc