Woodwork (part 1) Panelling Repairs

Woodwork (part 1) Panelling Repairs

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By James Mott

Introduction to Timber Panelling

Timber panelling is principally a form of decoration and it makes as dramatic an impact on the appearance of a room today as it did in Georgian times. As with any form of decoration it was historically an indicator of wealth and status. By the early Georgian period oak, cedar and walnut was very rare and found only in the wealthiest households. As the 18^th Century progressed less expensive softwoods were imported from the Baltic, collectively known as deal. Deal panelling was often painted both to imitate more expensive materials and to afford it more protection.

Panelling is constructed using a series of stiles and rails (the former being the vertical part of the frame, the latter the horizontal), which are grooved to accept panels. A panel is made up by gluing a series of two or three pieces, which together make up the width of the panel. They are usually constructed in softwood materials that are then painted or from hardwood materials such as oak and then polished. It is fitted to timber studwork or brickwork, and can be either full height, or finished at dado level.

Why do panels split?

Split panelling is a problem that is found in historic buildings and houses up and down the country. However, panels are designed to accommodate a certain amount of movement. The panel being situated within a groove formed within the framework, has no fixings so that the panel should be able to move. The groove is designed to allow the panel to shrink and expand within given parameters.

If the panelling becomes stuck in the groove then the shrinkage of the timber may cause the panel itself to split. The timber stays stable in its length, but is subject to movement across the width. For example a three foot wide panel could, quite easily shrink up to half an inch under normal conditions. It is therefore vital that, following repairs to woodwork within a property, temperature change is controlled and kept as stable as is practically possible. The environment that the panelling is installed in is therefore an important factor with how the timber reacts to heat and temperature change. Many of the problems seen today are centred on the introduction of modern heating systems, which directly effect movement within woodwork. Many historic buildings have installed controlled temperature systems to help create a stable environment.

In summary, panelling is affected by:-

a) Paint or polish acting as a glue and sticking the panel in one position

b) The panel being fixed in a position by inappropriate nailing

c) The timber warping or cupping in the groove fixing the panel in one position.

Methods of Repair

Repairs to panelling is most certainly a job for a skilled craftsman, the following is a theoretical guide only.

1) If there is access to the back of the panelling the panel may be removed from the frame by removing the timber forming the back edge of the groove. Once the panel is removed the edges of the panel and frame should be cleaned to remove bits of polish, dust or glue which may have built up over time. Where the panel has split the edges may be straightened and a new piece of timber inserted to widen the panel to its original width. Any timber inserted should be suitably seasoned and care taken to match the grain and colour as closely as possible. This is particularly important with work which is to be polished so that the repair looks as natural as possible.

Temporary battens may be secured to either side of the repair so that pressure can be applied to the joint to assist the gluing process and removed when glue is set. The repair should now be flushed off by using a suitable plane and finished off with a cabinet scraper. Once the panel has been widened it can be held back in what is now a rebate by either reforming the groove as was originally designed or by the use of toggles to hold the panel in position.

2) If access is not possible and there are applied mouldings fixed to the face of the framework to hold the panel in position then this can be carefully removed giving access to the panel. The panel can then be treated as above and then put in position re-fixing the surface mouldings. Under no circumstances should a craftsman attempt to nail through surface fixed mouldings into the panel as any fixing will again hold the panel in position as this will stop the free movement of the panel within the groove.

3) Where it is impractical or inappropriate to remove the panel a repair needs to be carried out in situ. This is the more likely scenario and is the most complicated procedure to carry out successfully.

First of all pieces of the panel within the groove need to be freed up, access should be gained where possible and debris etc removed. A thin blade or saw with no set on it can be inserted along the edge of the groove to help free up the panel in its position. Once the panels can move freely within the groove, the two parts of the panel should be moved to the outside of the frame. The two inside edges of the panel can now be straightened to form a parallel opening where a suitable new piece of timber may be inserted and glued in position. If the two edges of the split panel are in good condition and can be glued together without the panel becoming too small these may be carefully cleaned (there will be a build up of dust etc on these edges which glue will not adhere to). If appropriate, battens can be screw-fixed to either side of the split and cramps applied to the battens to put pressure on the glue joint. Once the glue is set the repair can be flushed off, ready for the appropriate finish to be applied.

4) The above methods of repair are based largely on situations where major splits and shrinkage have occurred. In the case of small splits that do not run the full length of the panel, a sliver of timber, shaped to the size of the split can be fitted. Minor splits and small holes in polished woodwork, can best be repaired with the use of a hard wax, which can be pressed into the crack/hole and finished flush with the face of the timber. Waxes are widely available in numerous colours and a suitable shade should be carefully chosen to match. It is generally not advisable to fill cracks or splits with a timber filler, because if there is any movement in the timber in the future, the fillers almost certainly will crack and fall out.

To strip or not to strip?

In recent times it has become fashionable to strip painted panelling down to bare wood for aesthetic value. Rarely was panelling constructed in softwood to be left unfinished and therefore the process of stripping the paint from the surface will usually reveal a large number of knots and timber defects. This is because our predecessors utilised inferior grade timber expressly because they were going to cover it up.

When restoring splits in panels it is unadvisable to completely strip the panel of paint or finish rather it is better to only remove the finish locally around the area to be worked on. This is generally done using a cabinet scraper. Once the repair is executed, if the panel is painted, the repaired area may be repainted or if polished the repaired area can be refinished using a stain and polish to match the original colour. This is a specialist area of expertise and a skilled polisher should be assigned to the task.

General care and maintenance

It is important to note that most cracks and splits that appear on panelling are either due to the panel not being able to move to the position it was designed to assume and/or because of expansion or shrinkage due to environmental conditions. It is therefore important that any finish that is applied to interior woodwork allows free movement and that the temperature within the environment is controlled and monitored as best is practical, or problems will reoccur.

Often problems occur with buildings which have been un-occupied for long periods or after construction work has taken place, in an unheated or damp environment. Heating should be introduced on a very gradual basis turning up a few degrees a day at a time to avoid rapid drying out. Very hot radiators, lighting, windows and wall heaters can all potentially cause problems for timber shrinkage. This may seem obvious, but in my experience almost every situation where there are problems with excessive shrinkage is due a badly situated radiator or years of heat generated by sunlight from a window without suitable blinds. It should also be noted that any alterations within a building will almost certainly have an effect on interior fitments.

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