How to build garage shelves

Inspired by a helpful YouTube guide. This walk-through is based on the UK video "How To Build Garage Shelving UK", which goes through the whole job from marking the wall to loading up the finished shelves. Useful to watch before you buy timber so you can see exactly what sizes you will need.

1. Plan the layout before buying anything

Measure the wall you want to shelve and decide how many shelves you need and at what heights. Standard shelf spacing of 400 to 500 mm suits most boxes, paint tins, and power tools. Deeper shelves (350 to 400 mm) are more useful but need more timber.

Sketch a quick plan showing the upright positions and shelf heights. Most people space uprights at 600 to 900 mm centres - wider gaps need thicker shelf boards to avoid sagging.

2. Choose your timber sizes

For the uprights and horizontal bearers, 75 x 50 mm sawn timber (also sold as 3 x 2) works well for shelves carrying boxes and tools. The shelf boards themselves can be 18 mm OSB, plywood, or CLS timber depending on what you want the surface to look like.

Rough-sawn timber from a builders merchant is cheaper than planed timber from a DIY shed and perfectly fine for a garage. Buy it a day or two before fitting so it can settle in the temperature of your garage before you cut it.

3. Mark out and fix the uprights

Use a spirit level to mark two vertical lines on the wall where the uprights will sit. Drill and plug the wall - most garage walls are block or brick and need a 7 or 8 mm masonry bit with a matching wall plug.

Fix the uprights with coach screws or No. 10 woodscrews at 600 mm intervals. Check plumb at each fixing point as you go, because a wall that looks flat often is not. Pack behind the upright with washers if the wall bows outward.

4. Fix the horizontal bearers

Cut the horizontal bearers to span between your uprights and screw them to the uprights at each shelf height. Use two screws at each joint. At this point you can check the bearers are level before cutting the shelf boards.

If the shelves run right across to the back wall, cut a rear bearer and fix it to the back wall too. That stops the shelf from bouncing and gives a much more solid feel.

5. Cut and fit the shelf boards

Cut your shelf boards to length and drop them onto the bearers. You do not need to glue or screw them down unless you specifically want a fixed shelf - loose boards are easier to remove later if the layout needs changing.

If you are using OSB, put the smooth side facing up. It is slightly more pleasant to sweep clean and less likely to snag a shelf's contents when you drag things out.

6. Check the load and spread heavy items

Do not pile everything heavy onto one shelf. Spread weight across the structure. Paint tins, car parts, and tools add up quickly. If a shelf starts to look bowed after loading, add an extra bearer in the middle span.

That said, a well-built timber frame on 600 mm centres will carry a surprising amount. The fixings into the wall matter more than the timber itself - a shelving frame is only as strong as its weakest bolt into the masonry.

When to call a handyman

Call Richard if the garage wall is an unknown material, if the wall is rendered and you cannot tell whether it's block or brick behind, or if the shelves need to carry something genuinely heavy like an engine or large compressor. It's also worth getting help if you're fitting shelves against a wall shared with a neighbour - drilling in the wrong place can cause problems you don't want.