David Jeffery

David Jeffery Repairs

Window And Joinery Repairs

THE CONSERVATION AND REPAIR OF WINDOWS, DOORS AND JOINERY

D. JEFFERY & COMPANY have many years experience dealing with repairs of a traditional nature, below is some information that you may find useful if you are considering repair or replacement.

The first line of defence in maintaining the appearance and condition of windows and external joinery is regular and correctly executed decoration. The exterior decoration is primarily for the protection of the timber, good quality materials and workmanship are as essential as regular and planned maintenance. However, there are times when the exterior surface deteriorates and moisture will penetrate the surface, when this happens decay mechanisms will quickly take hold. It is essential that the decay is cut out otherwise the problem may not be cured. Applying so-called rot treatments and patching up the decayed areas with filler is certain to fail in the long term. In the meantime the decay and moisture may have been trapped under the freshly painted surface, accelerating the decay process and forcing it to other components. Eventually the decay will become unrepairable.

WINDOW INSPECTION - Casement windows

Casement Window

On a fine day have a good look at the condition of your windows, usually the Southwest elevation will have suffered the most from weathering. Inspect the condition of the external window cill, if there are any signs of flaking or blistering paint it is likely that decay could be present. Using a sharp probe check the area to see if the timber is soft, if it is then decay is present and will need attending to if further damage is to be avoided. Use the probe around the jambs and mullions where they join the cill, check also the bottom rail and the lower section of the stiles on the casements (whether fixed or opening). These are the most common areas of decay in casement windows.

WINDOW INSPECTION - Sliding sash windows

Sash Window

Sliding sash window can only be partially inspected for decay as there are parts if the window which can only be accessed by removing the sashes, this is essential if a full inspection is to be made. On a fine day have a good look at the condition of your windows, usually the Southwest elevation will have suffered the most from weathering. Inspect the condition of the external window cill, if there are any signs of flaking or blistering paint it is likely that decay could be present. Using a sharp probe check the area to see if the timber is soft, if it is then decay is present and will need attending to if further damage is to be avoided. Check the outer lining and the base of the pulley stile to check if the timber is soft, also check the bottom rail and the stiles of the sashes, these are the most common areas of decay in sash windows.

CAUSES OF DECAY

If you find decay in the window it is important to understand the cause to make sure this has been dealt with before repairs are undertaken. Most decay takes a hold as a result of poor maintenance as mentioned earlier. However, there other considerations to be borne in mind. Check that there are no leaking gutters or downpipes nearby which may be discharging onto the window increasing the likelihood of damage. Check also for vegetation, climbing plants etc which can cause damage. Are there any telephone or aerial cables entering through the frame and have they been sealed? Cables should loop down below the entry hole so that water will discharge at the lowest point, before entry to the frame.

REPLACE OR REPAIR?

Most listed buildings or those within a conservation area will require listed building consent to replace any windows, this is usually only granted if the windows are beyond economical repair. Replacement would be considered the last option and would be resisted in all but the worst cases of decay. Even new replicated windows will not be made from the quality of timber that the original windows are. The conservation of the original fabric of the window will retain the character of the property and the original timber is usually far superior to modern fast grown timber. Historic glass has a character that cannot be replicated by modern equivalents and adds a certain charm that may be lost if windows are replaced wholesale. Repairs should be considered the first option provided that they are executed correctly.

REPAIR TECHNIQUE

Window Repair

After many years honing our techniques we are confident that our repair methods are cost effective and durable. It is important that certain guidelines are followed if the repair is to be effective and long lasting. Timber should be cut back to 50mm beyond the furthest point of decay. Timber used for repairs should be of the same species and grain pattern and density should be matched as closely as possible. Reclaimed timber is preferable for the repairs, if new timber has to be used it should be well seasoned and preferably slow grown with dense growth rings. All external joints should be undercut, preventing the ingress of moisture into the joint. All fixings should be non corrosive and fixed through from the inside wherever possible. Polymer gap filling adhesive should be used on all joints.

DECORATION

Modern paints are not as durable as the old lead based paints which are no longer used. Good preparation and application of the paint is essential if a durable finish is to be acheived. All new timber should be preservative treated and all unsound paint finishes should be burnt off and sanded down. a minimum of three coats of good quality primer, undercoat and topcoat should be applied in dry conditions. It is recommended that the windows are repainted each year for the first three years to build up a good protective coating. Once this has been achieved regular inspections should be made every three years and redecoration should be every five years at the most.

UPGRADING WINDOWS

Upgrading of windows can usually be achieved with the inclusion of draught excluder. In sliding sash windows this will reduce heat loss, improve draft resistance, ease rattles, prevent dirt entering and give a much more smooth operation of the window. Additional security locks can also be fitted.

CONCLUSION

Windows in old buildings form much of the character of the building. Inappropriate replacements or poorly executed repairs will spoil the visual appeal and possible de-value the property in addition to the possibilty of not complying with listed building legislation. Correctly executed repairs will provide a long term solutiuon to the problem and will retain all of the character and charm that appeals to so many. Following the guidlines above will ensure that the repairs will last for many years to come.

D. JEFFERY & COMPANY are committed to the conservation and repair of windows, doors and joinery in period, listed and historic property. If you would like us to survey your property please use the enquiry form on the contact page.