A shady, plant-covered pergola is a real treat on a hot summer's day, or the perfect spot for outdoor entertaining. Here, we show you how to build a pergola from a kit, which you can find at your local garden store.
A pergola is essentially a series of arches linked together to form a covered walkway. The framework provides the perfect support for climbing plants, such as fragrant honeysuckle and roses. Although often made from wood or metal components, many designers choose to use a wood frame kit, as shown here.
Building a pergola from a kit should take you about two days.
Unpack and identify all the pieces. Mark the layout of the pergola on the ground with pegs and string — use a combo square to check right angles (image 1). If the area is to be paved, lift and reuse the turf elsewhere.
Arrange the pieces flat on the ground to check the fit of the joints. Make adjustments as necessary. If the wood isn't predrilled, clamp the timber in a vice and drill holes for the screws and bolts (image 2).
To make an arch, attach each end of a cross-piece to the top of an upright post using galvanized screws or bolts. Support the wood on a board to help secure and align the pieces as you work (image 3).
Measure the distance between the upright posts at the top and bottom of each arch. Then adjust the posts until the spacing is the same and then nail wooden battening across them to prevent splaying (image 4).
Mark the two upright post positions for the first arch using spray paint. Dig out the holes, making them about 2 feet deep and 12 inches across (image 1). Fill with 4 inches of graded base (a combination of crushed stone and stone dust).
Ram the graded base firmly in place with a metal spike or pole. Place the upright posts in the holes. Make sure each post is even by holding a level against each of its four sides (image 2).
To hold the uprights vertical while you're concreting them in, tack a temporary wooden brace to a peg driven into the ground (image 3). Concrete the posts in place.
To position the second arch, lay a side piece of wood on the ground to work out the spacing. Mark the position of the post holes with paint (image 4). Allow for a slight overlap where the side pieces of wood will rest on the uprights.
Dig two holes for the uprights on the second arch. Do a final check on the relative position of the two arches by positioning the side pieces of wood on top of their respective uprights (image 1).
Using a level, check that the side supports are horizontal and the uprights are vertical before concreting them in position (image 2). Repeat the steps for constructing arches until all the arches are concreted in place.
Pour the the concrete and leave it to set for 48 hours. Screw or bolt all the side supports in place, securing the joints tightly together (image 3). Predrill holes to avoid splitting the wood.
Most pergolas have extra cross-pieces to strengthen the roof (these do not sit on uprights so are unsupported). Mark their position midway between the uprights (image 1). Predrill screw holes in each piece.
Screw or bolt the cross-pieces in place — you will need someone to hold them steady to stop them twisting when you're drilling (image 2). Check that all the fixings on the pergola frame are tight.
Position the roof beams on top of the cross-pieces (image 3). Mark and predrill holes, and then screw in place. Leave the bracing on the upright posts for three weeks until the concrete has completely set.
A system of wires attached to the upright posts of your pergola will give plants the support they need to start climbing. Fix screw eyes at 1 foot intervals around the four sides of an upright. Attach galvanized wire to the lowest screw eye, run it through all the eyes on the same side of the upright and secure it firmly to the top one. Repeat on the other three sides of the upright. Guide shoots of twining plants onto the wires; tie in shoots of stiffer stemmed climbers, such as roses.
Excerpted from Garden Design
©Dorling Kindersley Limited 2009