New Roofs — Design, Structure, Insulation & Finish
A new roof has to look right, keep the weather out and meet today’s standards for structure and energy. In Midhurst, we start with a measured survey, agree the roof form and finish, then build a straight, ventilated and well-insulated shell before laying tiles or slate. Details at eaves, valleys, ridges and penetrations are set out carefully so water has a clean path off the roof and the coverings stay secure in wind. You’ll get clear timelines, tidy workmanship and a roof that’s ready for Building Control sign-off.
Survey, Design & Regulations
We confirm spans, bearing lines and the chosen covering, then check manufacturer pitch limits, exposure zones and fix schedules. For Midhurst projects, structural layout is agreed (hand-cut or trussed), insulation and ventilation are designed to current guidance, and junctions to chimneys, dormers and parapets are detailed up front. This avoids on-site compromises and ensures the roof meets Part A (structure) and Part L (energy) requirements with sensible ventilation to control condensation.
Layout, Pitch & Loading
Ridge height, hip/valley positions and overhangs are set from drawings and checked on site for sightlines and gutter positions. Pitch is selected to suit the covering and location, with fixings specified for wind uplift and snow load. We keep batten gauges consistent to the ridge so courses land neatly at verges, abutments and roof windows.
Part L Insulation & Ventilation
Warm or cold roof build-ups are agreed early. Warm roofs place continuous insulation above rafters, improving airtightness and reducing cold bridges; cold roofs use between-rafter insulation with a vapour control layer and cross-vented voids. Over-fascia and continuous ridge vents are sized for airflow; airtightness tapes and collars are used around penetrations to keep moisture out of the structure.
Structure & Carpentry
Whether hand-cut or trussed, the frame is set out straight and square so coverings sit flat and lines read true for Midhurst homes. Rafters are sized to span without bounce; purlins, binders and bracing prevent twist and racking. Wall plates, straps and truss clips tie the roof to the structure and resist uplift. Openings for roof windows or flues are trimmed with doubled members and proper load paths.
Hand-cut Rafters, Hips & Valleys
Birdsmouths and seat cuts are set from a common template for even bearing; hip and valley rafters are sized correctly and supported on valley boards where needed. We keep true mitres at hips, align jack rafters to the gauge, and leave clean, square openings for dormers or rooflights.
Trusses, Purlins & Bracing
Factory trusses are installed to layout, braced diagonally and laterally to the manufacturer’s schedule, and restrained to masonry with straps. Purlins, struts and binders are added where spans demand, with bearings formed neatly so ceilings below remain level.
Dry-in Layers
Once carpentry is set, we make the roof watertight. Breathable underlay is laid with correct drape and laps; eaves support trays protect felt from sagging into gutters. Graded battens are fixed to the specified gauge with nails to BS 5534. Counter-battens are used where warm roofs or sarking demand a ventilated drainage plane.
Breathable Underlay & Battens
Membrane laps are set to exposure zone, sealed where required, and turned correctly at abutments and verges. Battens are straight, free from defects and marked for gauge so courses track perfectly; fixings are corrosion-resistant and sized to penetrate the rafter sufficiently.
Warm/Cold Roof Build-ups
Warm roofs receive continuous rigid insulation above rafters with taped joints and a ventilated counter-batten zone; cold roofs use between-rafter insulation with a continuous VCL to the warm side and 50 mm cross-vented void. We coordinate thicknesses so fascia lines, window upstands and lead details land correctly.
Coverings: Tiles & Slate
We lay coverings to the manufacturer’s spec, with neat cuts and fixings suited to exposure across Midhurst properties. Courses are kept parallel to the ridge; verges, hips and ridges are mechanically fixed. Lead or proprietary flashings are integrated as we build so nothing is chased in as an afterthought.
Clay/Concrete Tiles
Plain tiles, interlocking clay or concrete profiles are fixed to the correct headlap and nail pattern. We use dry-fix systems for ridges/hips where appropriate, and form neat mitres or bonnet hips to match the style. Eaves and top courses are set out to avoid thin cuts and maintain the bond.
Natural/Man-made Slate
Slate is graded for thickness, holed accurately and laid to gauge with stainless nails or hooks. Soakers and secret gutters are formed where needed; cut edges are kept to sheltered locations. The result is a flat, even surface with crisp lines to ridges and verges.
Valleys, Flashings & Penetrations
Water management is all in the detailing. We form secure valleys, correctly lap flashings to the weather, and use formed collars and thermal sleeves around penetrations. Every junction is planned so maintenance is simple and staining is avoided.
Leadwork to Code
Lead is specified by code for bay size, fixed to allow movement and protected with patination oil. Step flashings, back gutters and trays are chased and dressed cleanly; fixings are concealed and jointed with correct laps or welts to resist capillary action.
Roof Windows, Solar & Pipe Collars
Roof windows are set true to rafter lines with the manufacturer’s flashing kits and insulation collars. Solar brackets are fixed to structure with watertight flashings; pipe and cable penetrations use proprietary collars and are sealed to membranes to protect airtightness.
Eaves, Verges & Ridges
Eaves support trays, bird combs and over-fascia vents are installed before battens go down. Verges are finished with dry systems or neat mortar where specified; ridges/hips are mechanically fixed for security and ventilation. Fascia and soffit lines are kept straight so gutters run quietly with correct fall.
Dry-fix Systems & Ventilation
Dry ridge/hip and verge systems provide reliable mechanical fixings and continuous airflow. We set them straight, bed seals evenly and leave ridge lines tight and true—no rattles, no mortar cracking and a long, low-maintenance life.
Fascia, Soffit & Over-fascia Vents
Timber repairs are made before new fascias/soffits or uPVC replacements go on. Over-fascia vents maintain the airflow path; eaves trays protect membrane; gutters are aligned to falls and outlets. The eaves read as one tidy, efficient assembly.
Building Control, Warranties & Handover
We coordinate inspections for structure and insulation, keep photo records of hidden work and provide product data where relevant. On completion, projects in Midhurst receive care notes and a clear summary of materials and fixings used, with any manufacturer warranties registered.
Why Choose DM Jones Contractors
- ✓ Measured set-out, correct pitch and fix schedules matched to your covering and exposure.
- ✓ Warm/cold roof options designed for Part L with proper ventilation and airtightness.
- ✓ Straight, secure structure—hand-cut or trussed—with robust bracing and restraint.
- ✓ BS-compliant membranes and battens; dry-fix ridges/hips/verges for long life.
- ✓ Clean leadwork to code and careful detailing at valleys, windows and solar.
- ✓ Tidy eaves with aligned fascias/soffits and quiet, free-draining gutters.
- ✓ Clear timelines, photo records, Building Control coordination and itemised pricing.
Request a Roofing Quote
Send drawings or a few photos with rough dimensions, the covering you prefer and any leaks or issues you’d like solved. We’ll visit to confirm levels and details, advise on insulation/ventilation, and provide a clear, itemised quotation with programme and options for materials and finishes.
