A specialist contractor, not a general builder
Onsite Sealants Ltd has worked on buildings across Surrey and the wider South East since 2009. Waterproofing and sealants are all we do, which is why we get called in when something has already been tried once.
We work for homeowners on a single damp wall, for managing agents on multi-block programmes, and for main contractors who need a specialist package delivered to programme. The scale changes, the method does not: survey, specify, install, sign off.
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Four things we do not compromise on
Diagnose before you sell
We will not quote for a system until we know what is causing the water ingress. Sometimes the answer is a gutter, not a membrane.
Our own teams, not subcontractors
Directly employed, CSCS carded operatives who have worked together for years, so the standard does not change job to job.
Written guarantees
Specifications, product data and guarantee paperwork handed over on completion, not promised verbally on site.
Priced to hold
Fixed quotations. If something genuinely unforeseen turns up, we stop and agree it with you before carrying on.
Why building owners choose us
- 15+
- years protecting buildings in the South East
- 2,400+
- metres of joint sealed last year
- 10 yr
- guarantee on tanking installations
- 4.9/5
- average score across published reviews
- Property Care Association
- CHAS Elite
- Constructionline Gold
- CSCS carded
- £5m liability cover
Where we work
We are based in Guildford and work across Surrey, Hampshire, Berkshire, West Sussex and Greater London. Anything outside that, call us anyway and we will tell you honestly whether it is worth the travel.
Unit 7, Bramley Business Park, Guildford, Surrey, GU5 0ABTalk to someone who has done the job before
Tell us what you are seeing and we will tell you what it needs. Most surveys are booked within five working days.