Exterior Cladding in Norwich

Expert Exterior Cladding
in Norwich

Why homeowners start thinking about cladding

Exterior cladding does two things at once: it shields the wall structure behind it from rain, frost and wind, and it gives the building a fresh face without the cost of re-rendering or rebuilding. For many homeowners the decision to clad begins not with style but with a problem they have noticed and are not sure how serious it is.

Understanding the warning signs early saves money. Catching failing cladding before water gets into the wall behind it is far cheaper than dealing with the consequences once it has.

Warning signs that your existing cladding needs attention

If your home already has cladding fitted, there are specific things worth checking every year, ideally after winter when frost and driving rain will have done their worst.

• Gaps opening between boards. Timber and some UPVC boards move with temperature. Small gaps are normal. Gaps wide enough to see daylight through, or where the sealant has cracked and pulled away, need dealing with before water tracks behind the boards.
• Boards cupping or bowing outward. This is a classic sign of moisture trapped behind cladding. On timber it means the board has taken on water unevenly. On UPVC it usually points to incorrect fixing or a board that has been damaged and is no longer sitting flat against the batten.
• Dark staining running vertically from fixings. On timber cladding, rust bleed from failing screws or nails is a sign that the fixings have corroded. Once fixings fail the board is only held by the boards above and below it, which puts stress on those joints too.
• Paint or stain peeling from the back face of timber boards. If you can see the back of any boards during maintenance, peeling finish on the back face means moisture is getting in from behind, not the front. The substrate or counter-batten spacing may be causing a problem with ventilation.
• Green algae or black mould patches. Some surface algae is cosmetic and can be cleaned off. But persistent mould that returns quickly after cleaning suggests moisture is being held against the board rather than running clear. This often points to a ventilation gap that has been blocked or never installed correctly.
• Loose or missing boards at the base of the wall. The lowest course of cladding takes the most punishment from ground splash, frost heave and general impact. Boards that have sprung away from their fixing mean water can drive behind the whole run.

What causes cladding to fail in the first place

Most cladding failures come down to one of three things: poor installation, the wrong material for the exposure, or simply age.

Poor installation is the single biggest cause of early failure. A job done without a proper breather membrane behind the boards, without adequate ventilation battens, or with insufficient fixing centres will fail years ahead of its time regardless of the quality of the boards themselves.

Timber cladding that has not been maintained is particularly vulnerable. Softwood boards that are not re-treated every few years will start to absorb water rather than shedding it. Once moisture is sitting in the grain, frost turns that moisture to ice and the board begins to split from the inside out. Hardwood and modified timber products are more resistant but they still need the end grains sealed, particularly at horizontal cuts made on site.

UPVC cladding that was fitted ten or fifteen years ago was often installed using clip systems that have since become brittle. The clips themselves can snap in cold weather, releasing boards without warning. On exposed elevations this can happen after a single hard frost.

What a proper inspection should check

Before any new cladding goes on, the wall behind needs to be in a sound condition. A good installer will check for damp in the substrate, look at the condition of any existing membrane and assess whether the wall ties are sound if the property has a cavity. Fitting new cladding over a damp wall simply seals the problem in.

The fixings into the wall matter too. Cladding battens need to hit solid material, whether that is masonry, structural timber or a solid substrate board. Fixings into damp or crumbling mortar joints will not hold the system under wind load.

When to repair and when to replace

Replacing individual boards is sensible where the damage is genuinely isolated, the board profile is still available to match, and the substrate and membrane behind are sound. On older installations, matching profiles can be difficult and the membrane is often beyond its useful life anyway. A partial patch on a failing system tends to delay the problem rather than solve it.

If more than roughly a quarter of the boards on an elevation are showing signs of movement, staining or damage, a full strip and re-clad is usually better value over a five to ten year horizon than repeated patchwork.

Cladding work we carry out in and around Norwich

North Walsham Roofers install and replace exterior cladding on homes across Norwich and the surrounding area, including work in nearby Aylsham and Cromer. We work with timber, UPVC and composite board systems. Every job includes a thorough check of the wall behind before any new material goes on.

If you have noticed any of the warning signs above, call us to arrange a roof and cladding survey so we can give you an honest view of what needs doing and what can wait.