New builds and warranties
Weep holes are present on the front of a new house and missing over the rear openings. What water path is absent at the rear?
The water path that is absent at the rear is the weep, the outlet that should let water out of the cavity over those openings. The front has weep holes. The rear openings do not. Water that reaches a cavity tray, or the base of a cavity over a rear opening, has no seen route to the outside face. The survey has recorded that absence. It has not proved the cavity is already wet, and it has not tested the trays. NHBC describes Buildmark as a 10-year warranty and insurance product. The note has not opened a claim.
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?
Weep holes are the small openings in the outer leaf that drain a cavity tray or a cavity base to the outside. On a new house they are expected over openings where water in the cavity needs a way out. Seeing them on the front shows the detail was used there. Missing them over the rear openings means that path was not seen on that elevation. The surveyor did not open the wall to find a hidden tray, and did not hose the cavity.
Tell the developer that weep holes are missing over the rear openings while they are present on the front. Ask them to confirm the trays and to form the outlets, as their work, not as a design in this report. Ask the solicitor which warranty applies. NHBC describes Buildmark as a 10-year warranty and insurance product. The survey does not open a claim. Do not assume the front weeps prove the rear is the same. The note exists because the elevations differ.
What should you ask your surveyor?
- Which rear openings have no weep holes?
- Is the missing path the outlet from the cavity, rather than a proved leak inside?
- Were the front weeps only a comparison, not a test of the rear wall?
What are the typical next steps?
- Record the absent weeps as a rear-elevation note.
- Ask the developer to account for the outlets over those openings.
- Do not treat front weeps as evidence the rear is drained.
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
If the rear rooms are dry, are the weeps unnecessary?
Dry rooms on the day do not put weep holes in the outer leaf. The water path that is absent is still the outlet over the rear openings. The survey has not proved the cavity is wet, and it has not proved it will stay dry. Front weeps do not serve the rear. The note has not opened a warranty claim.
Can you form new weep holes yourself because the front has them?
Not as an instruction from this survey. The report recorded missing weeps at the rear. It did not design new holes, and it did not tell you to open the brick. Forming outlets is work for whoever is putting the detail right, after the trays are understood. The survey has not opened a warranty claim by noting the difference.