How To Build a Garage

Step-by-Step Instructions

1 Lay the concrete base

Prepare a suitable concrete base for the garage. The floor should be 100mm (4in) thick but the edges built up to 200mm (8in) thick to support the walls, and built on a sub-base of a minimum of 100mm (4in) well-compacted and levelled hardcore. Take the time to thoroughly check for any possible problems at this stage, as any slight problems at this stage will be magnified once construciton of the garage starts.

2 Support the lower sections

While the lower sections of the garage wall are being assembled, they will need to be supported outside by ‘buttresses’. These can be made using lengths of stout timber, angled (but not pushing) against the walls. These will hold the structure securely while other components are being added.

3 Erect second level

The second level of wall panels are erected and fixed to the first. Make sure you have safe and level access as you will be working at a height, and work from the inside of the structure. Once the roof cross members are in place, the structure will become more stable.

4 Raise roof sections

On a large-span roof, you will need the assistance of at least one (or ideally two) helper(s) to help you raise and slide the roof into position across the members. Position ladders inside the garage and work slowly and carefully. Do not overstretch when on a ladder, stop what you are doing, climb down and reposition the ladder if you feel you are overstretching.

5 The last roof section

The final roof section will need to be lifted and positioned from outside and from above. Never stand on the roof of any structure or you could fall through. Instead, use crawl boards to evenly distribute your weight.

6 Hang the door

Lastly, hang the door or doors. If you have selected double-hinged doors that open outwards, then these are hung as you would hang an external door. See the next page for advice on installing an up-and-over door.

Hanging a Garage Door

Traditional hinged doors require a substantial clearance area for them to open properly. An up-and-over door, on the other hand, retracts inside the garage and is ideal for use where a garage forms a boundary and where a door must not swing out.

Up-and-over doors are always counterweighted and are available as either tracked or untracked, or can be partially or fully retracting. The manufacturers of up-and-over doors produce them in a range of standard sizes that are quite specific in terms of the garage opening – this means the distance between the frame posts and the height measurement from the floor to the head member. Most doors will require a solid wooden frame to provide a strong fixing, but some manufacturers produce door systems complete with a metal frame that simply needs to be screwed into the surrounding brickwork. When a frame is included in the kit, the openings and the overall frame dimensions will be specified.

Note that if you are replacing old and worn hinge-hung doors with an up-and-over door, your old frame may not be a standard size and in this case you will need a made-to-measure replacement.

Up-and-over doors can be bought with a remote control opening and closing system that you can operate from inside your car. These are best installed by the manufacturer. See the next section for advice on buying automatic gates; the same principles apply to garage doors. Always remember to get a spare remote control for emergencies.

Step-by-Step Instructions For Hanging a Garage Door

1 Attach the mechanism

Follow the individual manufacturers’ instructions to attach the counterweight mechanisms to the sides of the garage door.

2 Position door

The most difficult step in fitting the door is raising it into position in the frame and then temporarily holding it there with props and wedges. If possible, get one or two helpers to assist you.

3 Fit the tracks

Once the door is propped and wedged securely in position and then fixed to the frame, the tracks (if your door system requires them) are fixed securely along the interior walls of the garage at the appropriate height.

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