Add a touch of class to your garden with this simple arch
By Bob Thickpenny
A garden arch can add a little class to an entrance or gateway or serve as a base upon which to grow a climber or climbing rose. It adds some structure to a garden environment.
The beauty of this arch is that it can be made in a weekend. This arch is very simply constructed but its design can be endlessly varied to suit the whim of the landscaper. It’s quite possible to use this with four posts and form an entrance. A few battens nailed across the arches will also form a trellis for a creeper.
The arch is constructed from 100mm x 100mm tanalised pine uprights with 50mm x 100mm struts and the arch itself is made from 18mm ply.
First mark out the arch shape on the ply. The width of the arch can be any dimension that you wish depending on the span you need and the plywood sheet size. In this case, we used a span of 1200mm. The arches are cut out roughly with a jigsaw and finished on a bandsaw. It is easier to handle the pieces rough-cut first rather than try to manipulate the whole sheet on the bandsaw.
Rough cutting the arch from the plywood sheet
Curves template
With the arches cut and sanded smooth, the laterals are cut to length and the curves marked at each end It is best to make a template for the curves to ensure they are all the same.
The arches sit on the laterals in 40mm slots 18mm wide. These I trench on a drop saw but they could be cut on a table saw in a series of cuts and then chiselled out.
The laterals have a 40mm deep notch which sits in a bridle joint on top of the uprights. The two mating notches keep the lateral rails square against the uprights. I usually cut this notch on the bandsaw to save time but it is also just as easily trenched on the drop saw or cut with a power saw and chiseled out.
Be accurate with your cuts to be sure to keep this joint tight. Once all the notches are cut I finish the ends by cutting the decorative curves on the ends and giving them a final smooth with sandpaper
Posts
The posts have a bridle joint cut in the top end which mates with the notch in the laterals.
This I usually cut on the drop saw. It requires quite a careful lining up to ensure that the post is square to the saw. Test it with a square.
The length of the post and its weight makes it mandatory that you have some sort of support to balance the post. I usually cut the notch on one side and then flip the post and cut it again on the reverse face and cut out the waste on the bandsaw.
The notch in the lateral helps to cover any imperfections in the base of the bridle joint. It also helps to strengthen the joint overall. I add four reinforcing supports between the lateral rails and the uprights cut from 150mm x 50mm scrap.
Again with this design, I have used the simple ogee but you are only limited by your imagination. With everything cut, it is time to begin assembly
Assembly
Start with the arches.
Fit each of them to the rails and check by eye that they line up with each other. It’s a good idea to do the first and last and then add the centre two, using the outer ones as guides.
I temporarily hold each arch in place with a nail and later use a stainless screw to secure them. Now secure the rails to the uprights and screw through the cheeks of the bridle joint with two screws. Add the curved support pieces again with screws. If you find the stainless screws too dear, it’s possible to use steel provided the holes are primed and filled later prior to painting.
Decorative
I sometimes add a little additional decorative elements in the form of a moulding to the upright posts, too. To assist with transport and with erecting the posts in the garden, I nail a temporary batten at ground level to the posts.
The posts can be concreted into position or bolted to a galvanised fitting that is concreted into position. If the posts are to be buried in concrete, ensure that the timber they are made of is either H4 or H5. If they are to be held in galvanised fittings, H3 is sufficient.
