Flat Roofing — Warm Roofs, Overlays & New Builds
A flat roof should be watertight, warm and tidy at the edges. We assess your existing deck and coverings, confirm falls and outlets, then recommend the right route—overlay or full strip and replace. As trained RESITRIX installers we deliver tough, single-ply EPDM systems with welded seams, and we also build GRP/fibreglass roofs where the brief suits. Details at perimeters, upstands and penetrations are set out carefully so water leaves the roof cleanly. Expect neat trims, correct insulation and a finish that looks sharp and lasts across Surrey, Hampshire and Petersfield.
Survey & Options
Every roof starts with a proper look: deck condition, moisture in the build-up, existing falls, outlet capacity and upstand heights. We discuss access, disruption and budget, then present clear options with pros, cons and lifespans. Where the existing membrane is sound and dry, an overlay can be cost-effective; where moisture or poor falls exist, a full strip with new insulation and tapered scheme pays back in performance and warranty. You’ll know exactly what we’re proposing and why—whether the property is in Surrey, Hampshire or Petersfield.
Overlay vs Strip & Replace
Overlays reduce waste and time on site, provided the deck is dry, solid and the upstands allow the extra thickness. We prepare the substrate, prime as required and install the new system with compatible trims. If tests show trapped moisture, rotten decking or inadequate falls, we strip back, repair the deck, introduce tapered insulation and rebuild with a full manufacturer-backed specification. It’s the right fix, not a quick cover-up, and our teams bring this disciplined approach to projects throughout Petersfield as well as further afield.
Insulation & U-values
Warm roofs keep the structure on the warm side, reducing condensation risk and improving comfort. We size insulation to hit sensible U-values for year-round performance, add vapour control layers to the warm side and tape laps for airtightness. At perimeters and rooflights we detail thermal breaks so cold bridges don’t print through. Where headroom is tight, we’ll balance thickness with tapered schemes and check door/threshold levels remain compliant—something we’ve delivered successfully for clients in Petersfield with varied property types.
Substrate Prep & Falls
Good membranes need a clean, sound base and water that knows where to go. We re-sheet or repair decks where needed, fix loose boards and plane high spots. Falls are corrected with tapered insulation or firring pieces so water runs to outlets, not towards door thresholds. Before membranes go down, we dry-sweep, vacuum and spot-prime as the system requires, leaving a dust-free, solid surface ready for long-life adhesion.
Tapered Insulation & Crickets
Tapered boards create consistent planes to outlets without heavy screeds. We design the layout to avoid bird-baths and add “crickets” behind rooflights, parapets and long drips to steer water around obstacles. Joints are tightly butted, staggered and mechanically fixed or adhered to spec, then sealed so wind can’t whistle under and telegraph lines through the finish.
Outlets, Overflows & Scuppers
Outlets are sized to the catchment and fitted with welded sump details to pull water down. We add secondary overflows where parapets could otherwise pond in heavy rain, and we form neat scuppers through walls with dressed flashings and drips. Leaf guards and accessible strainers are included so maintenance is simple and flooding risk is minimal.
RESITRIX EPDM Systems
RESITRIX combines EPDM durability with a weldable backing for strong, reliable seams. Sheets are positioned to minimise joints, then hot-air welded with testable seams. The system tolerates movement, resists UV and is excellent for complex shapes. We choose compatible primers and adhesives, and we document the install for manufacturer warranty where required.
Upstands, Corners & Terminations
Upstands are taken to the correct height (typically 150 mm above finished surface) and fully supported. Internal/external corners use prefabricated pieces or neat site-formed details, welded and probe-tested. Terminations at walls employ cover flashings or compression bars with sealants specified by the system, not generic mastic, so the edge stays tight for years.
Perimeters, Drips & Edge Trims
Perimeter trims give a crisp shadow line and controlled drip. We fix them to structure, not just thin fascia, and set laps to shed water away from the building. Drip edges align with gutters; where water must fall to a lower roof, we include splash protection and stop-ends. The visual result is clean and straight; the practical result is dry walls and quiet drainage.
GRP/Fibreglass Options
GRP provides a tough, seamless finish around small upstands and intricate edges. It’s ideal for smaller roofs, dormers and bays where a monolithic look is desired. We only install GRP over suitable, well-fixed decking, and we follow the resin schedule for temperature and cure so the surface doesn’t pinhole, craze or blush.
Decking, Resin & Topcoat
OSB3 or ply decks are fixed tight with correct fasteners and gaps. We lay mat to spec, wet-out consistently and roll for full consolidation without dry patches. Topcoats are applied at the right coverage for colour depth and UV resistance, with anti-slip added where foot traffic is expected. Trims are bedded and sealed so edges look factory-finished.
Expansion Breaks
Larger GRP areas need movement control. We introduce expansion breaks at set centres or changes in direction so thermal movement doesn’t crack the surface. Breaks are integrated into the patterning and trims, keeping the roof reliable without spoiling the clean look.
Rooflights & Penetrations
Daylight transforms spaces below. We fit lanterns, domes and sun pipes on insulated kerbs with welded or laminated upstands, and we flash them to the membrane system so warranties remain intact. Pipe and cable penetrations use proprietary boots and collars, sealed to the vapour layer beneath to protect airtightness as well as waterproofing.
Lanterns, Domes & Sun Pipes
Kerbs are set level with correct upstand heights; lanterns and domes are square, bonded and mechanically fixed. We allow for internal finishes, condensation control and cleaning access. On tapered schemes we “picture frame” insulation to avoid ponding against the kerb, keeping water moving to the nearest outlet.
Pipe Collars & Cable Boots
Penetrations are planned, not punched last minute. We install matching collars/boots, weld or bond per the system, and clamp where specified. Beneath, we seal to the VCL so warm moist air cannot track up into the build-up. Labels are left on services for future maintenance.
Testing, Warranty & Handover
Seams and details are checked as we go and again at completion. Where appropriate we flood-test controlled areas or use electronic leak detection on larger roofs. You’ll receive photos, product data, care notes and any manufacturer warranty. We explain simple maintenance—keep outlets clear, rinse debris—and note safe access points for future checks.
Why Choose DM Jones Contractors
- ✓ Honest survey with clear recommendations: overlay when suitable, strip when it’s right.
- ✓ Warm-roof build-ups designed for good U-values and condensation control.
- ✓ Corrected falls with tapered insulation, crickets and properly sized outlets.
- ✓ RESITRIX EPDM installed by trained hands; GRP delivered with disciplined cure control.
- ✓ Crisp perimeters, tidy upstands and tested seams for long-term reliability.
- ✓ Rooflights and penetrations detailed to the system so warranties stay valid.
- ✓ Flat roofing services trusted by homeowners in Surrey, Hampshire and Petersfield.
- ✓ Clean sites, clear communication and itemised, sensible pricing.
Get a Flat Roof Quote
Send a couple of photos (inside and outside), rough sizes and any pooling or leak notes. We’ll assess the best route—overlay or full rebuild—confirm insulation and falls, and provide a clear, itemised quotation with programme and warranty options. For customers in Petersfield, we can often arrange a rapid site visit to give practical, tailored advice.
