Outbuildings and conservatories
What should you ask if a lean-to greenhouse shares the house gutter?
Ask how the water is supposed to leave, and what the house wall shows. A greenhouse fixed to the wall often shares a gutter or throws water at the brickwork. The survey can describe that junction, a blockage and a stain. It cannot invent a planning class for the greenhouse, and it does not decide who owns the gutter.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
The defect, if there is one, is usually ordinary and local. A shared gutter that is undersized, a missing stop end, or a pane that dumps rain into the joint will wet the wall of the room inside. A home survey sees the staining and the gutter it can reach with its eyes. It does not water-test the run. The greenhouse frame can be rotten while the house gutter is the thing that overflows.
Keep ownership for the solicitor if the gutter also serves next door. Condition is still worth describing. Do not remove the greenhouse before exchange to see the wall, unless the seller agrees, because you may be taking off something you do not yet own. A clear pane is not a clear gutter.
What should you ask your surveyor?
- Does the greenhouse share the house gutter, or discharge against the wall?
- Is the house wall stained inside at that point?
- Are you inventing a planning class for the greenhouse?
What are the typical next steps?
- Point a builder at the junction and the gutter, not at a planning label.
- Photograph the stain and the outlet before anyone clears the greenhouse.
- Leave ownership of a shared gutter with the solicitor.
Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.
Also asked about this
Is a greenhouse a conservatory?
Not just because it leans on the house. Describe the structure that is there. Do not borrow the other name.
Does a new house gutter prove the greenhouse joint is sound?
No. The joint and the wall behind the greenhouse can still be unseen or wet.