How Do You Plan a Renovation in an Older Building?

What turns up most often?

Plumbing comes first. Galvanised pipe used in the building practice of the period narrows from the inside over time as scale and rust build up. A line that looks sound from outside can still deliver poor pressure at the tap, and this is usually why.

Wiring comes second. Circuits laid years ago were not planned for the number of appliances used today. Sockets are too few, cable sizes are thin for current loads, and in some flats there is no earth conductor at all.

Third is how true the floors and walls are. In an older property walls may not be truly vertical and floors not truly level. That creates problems directly in large format tiling and in fitting ready made cupboards. Levelling the surface is a separate item of work and it is identified at the survey.

How likely is a hidden leak in an older property?

Likely enough that it belongs in the planning. Pipework of the period reaches the end of its life, and a leak that has been running quietly can already have done damage before anything shows at the surface.

For an older property the practical consequence is this. Before the finishes are decided, the condition of the services should be established, because a leak found after the tiling is down means lifting that tiling again. Our separate guide on the signs of a water leak covers how to recognise one and how it is traced.

Should the plumbing be fully renewed?

The decision rests on the age of the line, the material and the visible symptoms taken together. There is no single rule, but one distinction works well in practice.

If the walls and floor are coming up anyway, leaving old pipework in place is a short term saving. Opening a newly finished bathroom again a few years later for a leak costs many times that saving. An open wall is the cheapest moment there is to renew services.

If the line is relatively recent and there are no symptoms, full renewal is unnecessary spending. In that case partial work is enough. We make that distinction at the survey, because the answer belongs to the property rather than to a rule.

Can structural elements be altered?

Load bearing walls, columns and shear walls carry the weight of the building. Altering them concerns the safety of the whole structure rather than one flat, and it is not done without a professional assessment.

In older buildings this is even more sensitive, because which wall is load bearing cannot always be judged by eye. Thickness is not a reliable guide. Given that this is an earthquake region, it is worth being firm on the point.

We do not take on work involving the structural system on our own account. No wall is opened before the necessary assessment, and if there is doubt the job stops there.

What should the survey look for?

In an older property a survey is more than taking measurements. The first thing looked at is damp and staining. A mark on a wall or ceiling points to another problem underneath it and widens the scope directly.

Next the services are examined. The material of the line, the behaviour of the meter and the existing pressure are assessed together. Whether there is a gas installation is also asked at this stage, because boiler and pipe positions are planned around it.

Third comes the joinery. The condition of windows and doors affects both insulation and scope. Joinery replaced after the renovation damages walls and finishes that have just been completed, so that decision is made at the start.

How do you reduce surprise costs?

Most surprise costs appear in older properties and they come from the same source, the real condition revealed when a wall is opened. They cannot be removed entirely, but they can be made predictable.

The method is simple. Ask the contractor what could turn up unexpectedly here. An answer that gives an honest list of possibilities is more trustworthy than one that says nothing will. A possibility discussed in advance is not a surprise.

The second method is to keep a margin in the budget. In an older property the scope growing a little is expected rather than exceptional, and setting that aside at the start makes mid job decisions easier.

The third is keeping the decision with you. When something unexpected appears, ask to be shown it first and to discuss the options and the cost afterwards. Nothing should be added to the scope without your approval.