There are some very elaborate structures around but, often, all that is required is a simple pergola design over which to grow a few beautiful climbing plants, or to sit under on a warm summer's day. Wouldn't it be great to 'knock one up' yourself, while your enthusiasm is high. But then - I hear you asking yourself - can I really do it? Well, the simple answer is yes!
A pergola is a fairly easy structure to build, if you can grasp the basics. The hardest part is measuring and cutting the rafters (those are the beams of wood that run across the top of the structure). If that process is simplified, it can save a great deal of time and effort. Lets have a look at some ideas to make life easier for ourselves -
Use a trellis panel for the rafters
A simple pergola usually has four posts, which support main rafters and cross rafters across the top. These rafters have shaped rafter tails, which extend beyond the posts. Getting them to slot into one another involves quite a lot of cutting so, instead of 'notching' all the rafters, try using a trellis panel to form most of them.
This is a very effective way of simplifying the process. The only rafters that will need cutting and notching are the main entrance and exit ones, and the side rafters - four, in all. The trellis panel is attached to the top of the posts, fitting snugly between the rafters.
Just one thing to remember: when attaching the pergola rafters to the posts, bolt them on a 'trellis depth' higher than the post, so that all will be flush across the top. Alternatively, screw the trellis panel on to the top of the posts first and then attach the rafters afterwards, to fit flush with the trellis sides.
This method is extremely effective, giving good shade, and ample support for climbing plants. Once the rafters are cut, and the posts secured, there is not much else to do, other than fix everything together.
Set the side rafters below the main rafters
By doing this, no notching is necessary, making the job even easier! The main rafters are bolted on, as above. Now place the side rafters flush with the underside of the main rafter tails. This means that the only wood cutting necessary is that needed for shaping the pergola rafter tails, which can be either a straight angled cut, using a hand saw, or a more elaborate curve, using a jig saw. Even though this does require some cutting, it is the fun part, where you can use your creativity to build a unique and beautiful structure.
Use laths as rafters
These don't look quite as substantial as the normal rafter, but nevertheless can look extremely effective. There is no need to notch the wood. The laths (approximately 2"x1" strips of wood) are just laid flat on the side rafters. This method seems particularly suited to corner pergolas, where all is needed is a corner brace in the corner apex of the structure, with the laths fanning out from this central point.
Use post anchors instead of concrete
Using concrete can ensure a very secure structure, but for a simple pergola design, using standard size wood, this is not absolutely necessary. The alternative is to use post anchors - or what used to be called Metposts and are sometimes called fence spikes - to anchor everything to the ground. Believe me, when everything is bolted and screwed together, nothing (apart from an earthquake or hurricane) is going to move it!
Do check for underlying utilities, though, as post anchors have long spikes, which can rupture cables and pipes, and are extremely costly to repair.
The advantage of using this method is that you don't have to wait for the concrete to dry, and can get on with the job, without having to worry if you have accidentally moved the post from upright. Also concrete can be messy, requiring washing of tools, clothes and spillages - and then, if you have mixed too much, you need to get rid of the surplus. Often post anchors can be a more convenient option.
It takes a little practice to get used to hitting them in, as they tend to skew round, but they are usually sold with a post anchor driving tool, which has a bar that can be turned to keep the anchor in line.
Taking everything into account, a simple pergola design might be the most suitable option. It can be a rewarding project, especially as, in a very short time, you will standing back to admire your creation, with a well-earned drink in your hand!
