The Roof Replacement Process, Step by Step

What Happens Before a Single Tile Comes Off

A proper roof replacement starts well before any scaffolding goes up. We carry out a thorough inspection first, checking the roof covering, the timbers underneath, the fascias and soffits, any lead flashings, and the condition of the chimney stack if there is one. This tells us exactly what needs replacing and what can be retained, so we can give you an accurate, itemised quote rather than a rough guess.

In Cambridge, we regularly find that older terraced houses and Victorian semis have battens and felt that are original to the property. Once we strip the tiles, decayed felt and split battens become obvious, and those need replacing before any new covering goes on. Skipping this step is how cheap jobs fail within a few years.

Scaffolding, Stripping and Protecting Your Home

Scaffolding is erected first and must be properly tied to the building. On a standard semi-detached Cambridge property this usually takes half a day. Once the scaffold is safe, we strip the old roof covering, working from the ridge down to the eaves and loading the waste into skip bags or a skip positioned on the drive or road, with any necessary skip permit arranged in advance.

Before stripping begins we protect your loft and interior by laying boards across the joists, so dust and debris do not fall through. Any items stored in the loft are best moved out beforehand. We board up any open sections of roof at the end of each working day so your home stays weathertight overnight.

The Structural Check and Preparing the Deck

With the old covering off, we inspect every rafter and purlin. In Cambridge's clay-heavy ground conditions, older properties can settle unevenly, which sometimes shows up as rafter sag or a ridge that has dipped. Minor movement can be packed and supported; more serious structural issues need a carpenter before tiling begins.

New roofing felt or a breathable membrane is laid across the rafters, starting at the eaves and lapping upward so water always sheds over the layer below. New treated timber battens are then nailed across the felt at spacings matched precisely to the tile or slate being used. This forms the framework that every tile clips or nails to.

If your property needs new fascias, soffits and guttering, this is the right moment to have them replaced, while the scaffold is already in place and the eaves are fully accessible.

Laying the New Roof Covering

Tiling or slating starts at the eaves and works upward in overlapping courses. Every tile in an exposed Cambridge location should be mechanically fixed, meaning nailed or clipped, not just laid and left to gravity. High-pitched roofs and gable ends need full fixing on every course. The National Federation of Roofing Contractors publishes guidance on fixing specifications, and we follow those standards on every job.

Lead flashings are dressed into abutments, around chimneys, and along any valleys as tiling progresses. This is detailed, time-consuming work and it matters enormously: flashing failures cause the majority of leak problems we see when we're called to repair other roofers' work. If you have a chimney, see our chimney rebuilds page for details on the pointing and repointing we carry out at the same time.

The ridge tiles are bedded and pointed last, sealing the apex of the roof. On older Cambridgeshire properties we often use a dry-fix ridge system rather than mortar, which handles thermal movement better and does not crack over time the way traditional wet-bedded mortar can.

Finishing, Inspecting and Clearing Up

Once tiling is complete we walk the entire roof, checking every ridge tile, every flashing and every course for anything that looks out of line. Valley troughs are cleared of tile off-cuts, gutters are refitted and checked for fall, and the scaffold is cleared of any loose material before it comes down.

A roof replacement on a typical Cambridge three-bedroom semi takes three to five working days from scaffold erection to clearance, depending on the size of the roof and what we find underneath. Flat sections or dormers add time. Weather plays a part too: we will not lay felt or tile in heavy rain or high wind, so we always keep you informed if conditions push the programme back.

Prices for a full replacement vary considerably with roof size, pitch, tile choice and the condition of the timbers, but as a broad guide most Cambridge homeowners should budget somewhere between £5,000 and £12,000 for a standard pitched roof on a semi or detached house. Flat roof replacements are priced separately per square metre.

Before the scaffold comes down, check the work from ground level and from inside the loft if you can safely do so. Look for daylight, consistent coursing, and clean pointed ridge work. If anything does not look right, flag it while the scaffold is still standing.

Ready to get the process started? Contact us for a free roof survey and quote for your Cambridge property, and we will give you a clear picture of what is needed and what it will cost before any work begins.

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