Measure the furniture, not the concrete. Work out the footprint of whatever will sit under the roof, add 60 to 90 cm on the sides people walk around, and that is your minimum. Then check what is already overhead and nearby, because eaves, door swings, air conditioner units and pool equipment decide the height and the setbacks far more often than the furniture does.
See the size menu on our motorized louvered pergola
Start with what goes underneath
Set the table and chairs out the way you actually use them, chairs pulled out rather than pushed in, then measure the rectangle they occupy. A six-seat dining set with everyone seated takes roughly 3 × 3 m. A lounge setting with a sofa and two armchairs runs wider and shallower. An outdoor kitchen with a counter and a walkway behind it is deeper than most people guess.
Add your walking clearance and you have the number to shop with. Skipping this step is how people end up with a roof that covers a beautiful expanse of unused slab, or one that stops just short of the chair backs so anyone at the end of the table gets wet.
Width versus depth
Our size menu lists width first, depth second. Width is the dimension across the front of the structure, depth is how far it comes out from the house or from the back of the patio. Both matter, and they are not interchangeable when you order.
One thing worth asking before you commit: which way do the blades run. It changes the shadow pattern across the space at different times of day, and light falling in stripes along a dining table is a different experience from light coming across it. Ask us to confirm the blade direction for your unit rather than assuming.
Height, and what hangs below
Standard post height on our units is 2.7 m (8'10"), which leaves room to hang a ceiling fan or an infrared heater under the beams. If you want a fan, check the drop of the fan itself and the clearance code in your area, because a fan blade too close to the floor is a safety problem and a heater mounted too low scorches the people under it.
Height is also where existing structures push back. A pergola under a first floor window, or under the eaves of the house, has a hard ceiling it did not choose.
The clearances people forget
Walk the site and look for these before you measure anything:
- Doors that swing outward, and sliding door tracks that need clear floor.
- Gutter downpipes and the ground they discharge onto.
- Air conditioner condensers, which need airflow around them and make noise you do not want trapped under a roof.
- Pool pumps, filters and gas meters, which need access for servicing.
- Trees overhead. Anything that drops leaves into the drainage channels is a maintenance commitment, not just shade.
- The barbecue. A closed roof holds smoke. Putting the grill directly under it sounds convenient until the first time you use it.
None of these are dealbreakers. All of them are cheaper to plan around than to discover after delivery.
The base has to be level
Four posts carrying a rigid aluminum frame need to land at consistent height. Paving that has settled, or a slab laid with a fall for drainage, will show up as a gap under one post and a frame that is out of square. Out of square means blades that do not close evenly, which is where the leaking complaints start.
If your surface is uneven, plan to fix it or to shim and pack the footings properly. This is not the place to improvise.
When one unit is not enough
Our four-post layout covers 3 m, 3.5 m or 4 m in width and 3 m to 6 m in depth, which is 21 standard combinations from 3 × 3 m up to 4 × 6 m. Past those spans you move to the six-post layout, which reaches 8 × 6 m or 12 × 4 m, and units can also be linked in series to cover a long terrace with one continuous roof.
Bigger is not automatically better, though. A very large roof over a small seating group starts to feel like a warehouse rather than a room, and it brings more wind load and more permit scrutiny with it. Match the roof to the furniture, then stop.
How to read the size menu
Pick the standard combination that covers your furniture zone with clearance to spare. If none of them fit, or your site is irregular, choose Custom Size and send us your measurements. Those listed dimensions are spans to work within rather than a fixed set of options, so if you need 3.8 × 5.2 m that is a normal request and not a problem.
Measure twice here. A made-to-measure frame cannot be resold to anyone else, so a mistake is not returnable.
Frequently Asked Questions
How much space do I need around a dining table under a pergola? Enough to pull a chair out and walk past it, which for most settings is 60 to 90 cm beyond the table edge. Less than that and people shuffle sideways every time someone stands up.
Can a louvered pergola attach to the house? Our units are freestanding and carried on their own posts. If you want one anchored to a wall over a patio, send us the site details and we will tell you what is possible, because the fixing method depends on what the wall is made of.
What height do I need for a ceiling fan? Standard 2.7 m posts give you the room. Check the fan's own drop length and your local clearance requirement before buying, since those two numbers decide whether it works in your space.
My patio is not a rectangle. Can I still get one made to fit? Yes. Custom Size exists for exactly this. Sketch the shape, mark the dimensions and any obstacles, and send it over. Irregular sites are more common than you would think.
Where do the posts sit? At the corners of the footprint you order. If you are fitting the structure between walls or against a boundary, account for the post itself rather than measuring edge to edge of the open space.
Does a larger pergola need a stronger foundation? Generally yes, because wind load scales with the roof area. The footing requirement depends on your soil and your local wind values, which is a question for your building department or your contractor rather than for us.