Gosport at a glance
- Postcode districts
- PO12, PO13
- Population
- about 81,952 (GeoNames)
- Council area
- Gosport Borough Council
- Building approval
- Gosport Borough Council building control, or a registered building control approver
- Nearest main town
- Portsmouth, about 2 miles
- Guide price region
- South East (+10% on West Midlands rates)
What does a balcony or terrace in Gosport need?
A roof terrace in Gosport may be re-waterproofed when the owners want to change the finish, swapping old tiles for decking or porcelain on pedestals. Lifting the surface exposes the membrane, and replacing it then avoids having to lift the new finish again later.
Around Gosport, flat roofs are common on 1930s semis with flat-roofed garages and kitchen extensions and on bungalows with flat-roofed side extensions and dormers. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain.
How much does balcony or terrace waterproofing cost in Gosport?
For Gosport we use South East rates: £2,100–£3,600 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 | £2,100–£3,600 |
| Single garage (18 m²), EPDM rubber | £1,750–£3,100 |
| Extension (20 m²), GRP, new deck + insulation | £3,300–£5,900 |
How are thresholds, drainage and paving handled on a terrace?
They are designed together, because most balcony leaks start at the door threshold, a blocked outlet or a fixing driven through the membrane. Getting those three right matters more than the brand of membrane.
Thresholds: upstands are usually 150 mm above the finished surface, but a level or low step-out door cannot always achieve that. Where the upstand has to be reduced, extra protection is needed, such as a drainage channel at the door and a fall away from it, and the membrane must still run up and under the door sill.
Drainage: every terrace needs a reliable way off for water, with outlets sized for the area and an overflow if one outlet could block. Outlets under paving need access for cleaning.
Inverted roofs and pedestals: on an inverted roof the insulation sits above the waterproofing and is held down by paving or ballast, protecting the membrane from sun and foot traffic. Adjustable pedestals lift paving slabs level above the falls, so water drains underneath and the surface stays flat. Balustrade posts are fixed through upstands or side-fixed where possible, with every penetration sealed into the membrane.
What's included?
- Free survey of the deck, falls, outlets and door thresholds
- Strip-out of the failed membrane and deck repairs
- Sealed details at doors, outlets, walls and balustrade posts
- New liquid, GRP, single-ply or asphalt waterproofing
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
- Portsmouth · 2 mi
- Fareham · 4 mi
- Hayling Island · 7 mi
- Waterlooville · 7 mi
- Havant · 8 mi
- Emsworth · 9 mi
Balconies and roof terraces in Gosport: questions
Do you cover Gosport?
Yes. Gosport is part of our Hampshire coverage, including postcode districts PO12, PO13. 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 Gosport?
Where the work needs approval it goes to Gosport Borough 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 Gosport?
£2,100–£3,600 for a 12 m² balcony in a liquid-applied system including scaffold, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Why is water coming through the ceiling below my balcony?
The usual causes are a failed door threshold, a blocked or poorly sealed outlet, or a fixing through the membrane. A survey, sometimes lifting paving, finds the source.
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.