Who this guide is for
- Homeowners adding stone veneer to a facade or feature
- People with damp behind an existing stone veneer
- Renovators planning veneer with proper drainage
- Anyone briefing a mason on veneer detailing
Veneer is not waterproof
Stone veneer, like brick veneer, lets water pass behind it, so the wall is designed to catch that water and drain it out, not to keep every drop off the surface. Assuming the stone is the waterproof layer is the root of most veneer problems. The drainage path behind is the real defence.
The drainage path and weeps
Behind the veneer sit a barrier and a drainage gap, and weep details at the base let collected water escape. Sealing the weeps or omitting the gap traps moisture. Planning the drainage path and weeps is the heart of a durable stone veneer.
- A weather barrier behind catches penetrating water
- A drainage gap lets water move down and out
- Weeps at the base let collected water escape
- Sealing the weeps shut traps moisture
Attachment and support
Veneer has to be attached and supported correctly, with the weight carried and the stone tied back to the wall, which differs between natural and manufactured systems. Poor attachment is both a moisture and a safety issue. Plan the attachment to suit the system and the wall.
Openings, base and transitions
Where veneer meets windows, doors, the ground and other materials, the detailing has to keep water shedding outward and stop it wicking up from the base. These transitions are common weak points. Plan how the veneer starts, stops and meets openings.
Specialist work and damp signs
Stone veneer moisture detailing and attachment are specialist masonry work, and damp or efflorescence behind veneer should be assessed rather than sealed over. A qualified mason should design and install it. Requirements vary by location and project, and trapped moisture is not a DIY fix.
Stone veneer planning checklist
- 1Recognise veneer lets water behind it and must drain
- 2Plan the weather barrier behind the stone
- 3Provide a drainage gap and weep details at the base
- 4Keep weeps open, never sealed shut
- 5Plan attachment and support to suit the system
- 6Detail openings, base and transitions to shed water
- 7Stop water wicking up from the base
- 8Use a qualified mason for the moisture detailing
Common mistakes to avoid
- Assuming the stone surface keeps all water out
- Omitting the drainage gap behind the veneer
- Sealing weep holes shut and trapping moisture
- Poor attachment risking both moisture and safety
- Letting the veneer wick water up from the ground
- Sealing over damp behind veneer instead of assessing it
When to involve a professional
- Use a qualified mason for veneer attachment and moisture detailing
- Treat the barrier, drainage and weeps as weather-critical
- Have damp or efflorescence behind veneer assessed, not sealed over
- Confirm attachment and support suit the wall and system
- Requirements vary by location and project; verify with your professionals
Frequently asked questions
Questions readers ask about this topic
Is stone veneer waterproof?
No. Like brick veneer, stone veneer lets water pass behind it, so the wall is designed to catch and drain that water rather than keep every drop off the surface. Assuming the stone is the waterproof layer is the root of most veneer failures.
Why does stone veneer need weep holes?
Weeps at the base let water that gets behind the veneer escape from the drainage gap. Sealing them shut, or omitting the gap, traps moisture against the wall, which is why keeping the weeps open is central to a durable veneer.
What's behind a stone veneer wall?
A weather barrier and a drainage gap that catch and channel out any water getting past the stone, with weep details at the base. This drainage path behind the veneer is the real water defence, not the stone surface itself.
I have damp behind my stone veneer. What should I do?
Have it assessed by a qualified mason rather than sealing over it, because damp often means the drainage path or weeps aren't working. Trapped moisture is a specialist issue, and requirements vary by location and project.
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