Lean-To Pergolas: Off the House Wall
A lean-to pergola is fixed to the house along one side and stands on two or three posts at the front. It uses less material than a freestanding one and puts the shelter right outside the back door. Everything depends on the wall fixing: solid block is simple, insulated render and timber frame need brackets made for them.
The wall, the fall and the door.
Free, no obligation. One local company prices it, not five.
- 2 or 3posts at the front
- Away from the housewhich way the roof falls
- from €2,500aluminium, made and fitted
How it meets the wall
| Your wall | How it's fixed |
|---|---|
| Solid block or brick | A wall plate bolted through with resin anchors |
| External insulation under render | Stand-off brackets that reach the block behind without crushing the insulation |
| Timber frame | Fixed to the studs, or kept off the wall on its own posts |
| Not sure | A freestanding pergola set just clear of the wall |
The fall, and the flashing
A roofed lean-to falls away from the house, so water runs to the front. Where the roof meets the wall, a flashing stops rain running down behind it. Skip the flashing and the wall stays wet all winter.
Doors and windows
- The beam must clear the top of the back door and any window that opens outwards.
- Keep it below upstairs window sills.
- Check where the downpipes and the boiler flue are before fixing the wall plate.
What a lean-to costs
| Job | Typical cost | What moves the price |
|---|---|---|
| Timber pergola kit, 2.4 m square to a 3.4 m corner | €428 to €733 | Size and timber. Fitting and a base are extra |
| Aluminium louvred pergola kit, 3 × 3 m to 4 × 3 m | €1,886 to €2,998 | Size and maker |
| Made-to-measure aluminium pergola, supplied and fitted | from €2,500 | Size, roof, sides, base and fixings |
A lean-to is usually made to measure. Kit prices are for scale.
Planning
- Behind the house. Not in front of the front wall.
- 30 m² in total. The pergola plus every shed, garage, greenhouse and garden structure already there.
- 25 m² of garden left to the back or side of the house.
- 3 m high, or 4 m with a tiled or slated pitched roof.
Those are the Class 3 limits for garden structures, as amended by S.I. No. 338 of 2026. A protected structure or a house in a conservation area is a question for the council. The full rules are on our sister site, pergolabuilders.ie.
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Aluminium pergolasKits €1,886 to €2,998. Fitted from €2,500.
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Pergola ideasTwelve that suit an Irish back garden.
Pergola pricesFrom a €428 timber kit to a €7,420 motorised roof.Pergolas in every county
- Carlow330 mm of rain, May to September
- Cavan402 mm of rain, May to September
- Clare450 mm of rain, May to September
- Cork384 mm of rain, May to September
- Donegal445 mm of rain, May to September
- Dublin306 mm of rain, May to September
- Galway475 mm of rain, May to September
- Kerry445 mm of rain, May to September
- Kildare345 mm of rain, May to September
- Kilkenny333 mm of rain, May to September
- Laois360 mm of rain, May to September
- Leitrim414 mm of rain, May to September
- Limerick387 mm of rain, May to September
- Longford389 mm of rain, May to September
- Louth333 mm of rain, May to September
- Mayo488 mm of rain, May to September
- Meath347 mm of rain, May to September
- Monaghan374 mm of rain, May to September
- Offaly354 mm of rain, May to September
- Roscommon401 mm of rain, May to September
- Sligo481 mm of rain, May to September
- Tipperary372 mm of rain, May to September
- Waterford374 mm of rain, May to September
- Westmeath357 mm of rain, May to September
- Wexford365 mm of rain, May to September
- Wicklow319 mm of rain, May to September
Pick your pergola
Four taps: the type, where it's going, the size and the help you want. You see our price guide for it. Your number is only asked for at the end, if you want one pergola company that covers your county to ring you.
Questions people ask
Is a lean-to pergola cheaper than freestanding?
Often a little: two fewer posts. The wall fixing can add it back on an insulated wall.
Can it go on a bungalow?
Yes, if there's height under the eaves. Otherwise it's set on its own posts in front of the wall.
Does a lean-to need planning permission?
Not if it fits the limits: behind the front wall, 30 m² in total, 3 m high.
Get a price for a pergola in your garden
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