Exterior Cladding in Cambridge

Expert Exterior Cladding
in Cambridge

What exterior cladding actually does

Cladding is a protective skin fixed to the outside of a wall or dormer. It keeps driven rain off the structure beneath, reduces heat loss where it sits over insulation, and changes how the building looks. Done well, it should last decades without much attention. Done badly, or left to deteriorate, it lets water in behind the boards and into the wall itself.

We fit and repair timber, fibre cement and composite cladding on houses, extensions and outbuildings based out of Haverhill. Cambridge homeowners contact us when they spot something that does not look right and want to know whether it needs urgent attention or can wait until a planned renovation.

Warning signs that your cladding needs attention now

Cladding problems rarely appear all at once. They start small and get worse the longer they are left. Knowing what to look for means you can catch an issue before it becomes expensive.

• Paint peeling or bubbling from the face of boards. This happens when moisture is working its way out from behind the board, not just weathering on the surface. If you repaint over it without finding the source, it will peel again within a season.
• Boards that are visibly bowed, cupped or twisted. Timber cladding moves with moisture. A board that has warped significantly has absorbed more water than it should, usually because the back face was not primed before fixing, or because fixings have failed and left a gap at the joint.
• Dark staining that runs vertically down the wall below a board joint. This is a classic sign of water tracking behind the boards. The staining appears on the render or masonry beneath the cladding when water is entering at a joint, a window surround or a corner trim.
• Soft spots when you press a board. Any softness in timber cladding means rot has started. Press gently with a finger or a blunt screwdriver. Sound timber is hard throughout. If it gives at all, the fibres have broken down and the board needs replacing, not filling.
• Gaps opening between boards or at the corners. Joints that were tight when fitted open up as timber dries, or as sealant fails. A gap of more than a couple of millimetres at a butt joint or a corner is wide enough to let wind-driven rain in.
• Rust streaks below fixings. Stainless or coated fixings should not rust. If you see orange streaks running down from the nail or screw positions, the fixings used were not suitable for exterior use. This is common on older installations. Rusting fixings eventually fail entirely, and boards become loose.
• Cladding that feels hollow or moves when touched. If a section flexes noticeably or sounds hollow when tapped, the batten behind it may have rotted away. The boards themselves can look fine from a distance while the whole fixing structure behind them has gone.

What causes these problems in the first place

The most common underlying cause is poor installation rather than the material failing on its own terms. Timber cladding needs to be back-primed before it goes up, fixed with correct stainless or hot-dipped galvanised fixings, and detailed carefully at every junction with windows, soffits, corners and ground level. Skipping any of those steps shortens the life of the whole installation dramatically.

A second common cause is inadequate ventilation behind the boards. Cladding is supposed to be a rain screen, not a sealed panel. There needs to be a ventilated air gap between the back of the cladding and the wall or breather membrane behind it. Without that gap, moisture that does get in has nowhere to go and starts to cause damage from the inside.

Sealant and trim failure is the third area where problems start. The sealant around window reveals, at the base of dormers and at abutments with the roof is under constant movement from thermal expansion and UV exposure. Most sealants have a practical life of eight to twelve years before they crack or peel away from the substrate. Once that seal breaks, water finds a direct route behind the cladding.

On dormers specifically, the junction between the cladding and the roofing material is a particularly vulnerable point. Lead flashings and drip edges at the top of a clad dormer need to be in good condition for the cladding below them to stay dry. If the flashing has lifted or cracked, water runs straight down behind the boards and you may not see the result at wall level for months.

When to repair and when to replace

Isolated board failures, failed sealant joints and loose fixings are all repairable without touching the rest of the cladding. If fewer than roughly a quarter of the boards on a face are affected, repair is usually the right call.

If the batten structure behind the boards has rotted significantly, or if corrosion from wrong fixings has spread through most of the installation, full replacement is more cost-effective than chasing individual repairs. You would also be looking at replacement if the original installation had no ventilated cavity, since adding one properly means removing the boards anyway.

Ask any contractor to show you the battens and the wall behind a sample section before they price the work. That tells you whether what looks like a surface problem is actually a structural one.

What a proper repair or replacement job looks like

For repairs, the affected boards come off and the battens behind them are checked. Any rotten timber is cut out and replaced. New boards are back-primed on all faces before fitting, fixed with the correct stainless fixings, and finished at every joint with an exterior-grade flexible sealant or purpose-made trim.

For a full re-clad, we strip back to the wall, check the substrate, fit a breather membrane if one is not already there, run new treated battens, and fix the new boards with appropriate fixings for the material. We then re-detail every junction with windows, corners, soffits and roof abutments.

If you have noticed any of the warning signs above on a property in Cambridge or nearby, call us for a roof and cladding survey so we can tell you what is actually happening before you decide anything.