Caernarfon at a glance
- Postcode districts
- LL55
- Population
- about 9,730 (GeoNames)
- Council area
- Gwynedd Council
- Building approval
- Gwynedd Council building control, or a registered building control approver
- Nearest main town
- Bangor, about 8 miles
- Guide price region
- Wales (−8% on West Midlands rates)
What does a balcony or terrace in Caernarfon need?
Balcony membranes in Caernarfon wear out like any roof, but faster where they are exposed to foot traffic, furniture and planters. Once the topcoat has worn through or cracked around posts and edges, a full re-waterproofing usually lasts longer than repeated patching.
Caernarfon's flat roofs are mostly on lock-up garage blocks on estates, with plenty on 1930s semis with flat-roofed garages and kitchen extensions too. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof.
How much does balcony or terrace waterproofing cost in Caernarfon?
For Caernarfon we use Wales rates: £1,750–£3,000 is the guide for a 12 m² balcony in a liquid-applied system including scaffold, VAT included. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Balcony (12 m²), liquid-applied, scaffold | £1,750–£3,000 |
| Single garage (18 m²), EPDM rubber | £1,450–£2,600 |
| Extension (20 m²), GRP, new deck + insulation | £2,750–£4,950 |
How long does it take to waterproof a balcony?
A small balcony is typically waterproofed in two to four working days, plus time for scaffold if it is above ground floor. Liquid and GRP systems need dry weather and cure time between coats, which sets the pace.
The balcony door will be out of use while the membrane is laid and curing, and the room behind may be noisy while old paving or screed is broken out. If the team needs to work through the house, we agree a route and protect floors. Larger terraces with paving or decking take longer, because the finish has to be lifted and reinstated. Resin systems smell while they cure, so nearby windows are best kept closed.
What's included?
- Free survey of the deck, falls, outlets and door thresholds
- Strip-out of the failed membrane and deck repairs
- Written workmanship guarantee, with approvals handled where needed
- Lifting and setting aside of existing paving or decking
Building regulations in Wales
The Welsh Approved Document L applies. Renovating more than half of a roof over a heated room means upgrading it to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K. Welsh Government guidance is that most re-roofing needs building control approval, so check whenever more than a quarter of a roof is replaced or repaired. We deal with the application as part of the job. More on the rules.
Which nearby areas do we also cover?
Balconies and roof terraces in Caernarfon: questions
Do you cover Caernarfon?
Yes. Caernarfon is part of our Gwynedd coverage, including postcode districts LL55. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Caernarfon?
Where the work needs approval it goes to Gwynedd Council building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does balcony or terrace waterproofing cost in Caernarfon?
£1,750–£3,000 for a 12 m² balcony in a liquid-applied system including scaffold, at Wales guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Do you install balustrades?
Our work is the waterproofing and drainage. We detail the membrane around balustrade fixings so they stay watertight, and we can advise on where posts should be fixed.
What is an inverted roof terrace?
It is a terrace where the insulation sits above the waterproofing, held down by paving or ballast. The membrane stays protected and at a steadier temperature.