Building in easy access to services can reap big dividends

Our second bedroom is known locally as ‘the fridge’. By ‘locally’ I mean ourselves and our neighbours in the other half of the semi-detached property we inhabit.

Like ours, their second bedroom was sited over an integral garage. It also faces directly north in a relatively exposed location. And since our houses were built in the 1950s no insulation was ever fitted below the bedrooms’ tongued and grooved floorboards. As a result, both second bedrooms became iceboxes during the winter months.

The neighbours solved this problem by extending into the garage to create a second bathroom and utility room below.

We added a bay to the front of our house, including a window in the second bedroom, thus making its northerly aspect even more exposed.

Admittedly, this was done to match the facade with that of a self build we were erecting next door. But, apart from the metre or so depth of the new bay, the floor went undisturbed. So did the cold. This winter, after much prompting, I finally decided to do something about it.

I started by lifting the chipboard panels which form the flooring of the bay addition. Two things were immediately obvious. The first was that there was no insulation. The second was that the empty space had not gone to waste.

Or rather it had. Brick and block rubble, chipboard and timber offcuts, odd scraps of copper pipework and a selection of fag ends littered the area between the joists. The best part, in fact, of a rubble bag full.

Now this isn’t intended to be a moan at the slapdash habits of builders. If it was, I’d be honour bound to mention the odd pieces of rubble, rusted scaffolding and rotting offcuts steadily unearthed in the garden for months after our build was finished.

Rather, I was prompted to consider tidiness. Not, thankfully, in the home. I mean in the arrangement of, and access to, its services.

Further explorations of the original flooring revealed floorboards that seemed to have been lifted and replaced at random. Stretches of relatively new wiring and central heating pipework were clearly involved. But the general impression was that whoever had made these upgrades had been searching around for the best place to start.

In other words, there was nothing externally to help them out. No painted line to indicate a pipework run or joint, no handy diagram, setting out precisely where wiring, pipework and other services ran.

Generally, of course, it’s only selfbuilders and supervising architects who are able or willing to create such useful records. Renovators or converters – most homeowners, in fact – have to resort to first principles.

“In years to come contractors will thank you for it, and so will your wallet.”

In practical terms that means the Building Regulations, which have numerous requirements for the way cables, pipework and other structural intrusions should be run through a building.

For example, holes drilled through a joist should be on the centre line and no wider than 0.25 times the depth of the joist. Generally, too, wiring from a switch or power point ought to run vertically either to the ceiling or the floor and be buried at least 50mm in plaster.

Whether any of this actually happens, especially in older buildings, is a moot point, but at least it suggests where to look first.

In newer builds, particularly timber frames, one way to keep things tidy and accessible is to incorporate a service void. This consists of a second layer of plasterboard on the internal side of the external walls. Fixed on battens, it creates a void, typically about 50mm deep, through which pipes and cabling can be run easily and unobtrusively.

New builds, including extensions, can also take advantage of I-joists. Instead of solid timber, these are made from narrow lengths of engineered wood connected by OSB, plywood or an open metal web.

Since the strength of a joist is at its edges, relatively large openings can be drilled safely in the OSB or plywood, while the metal connection leaves the central space virtually clear. Plenty of room to fit, and work on, anything from electrical cabling to large ventilation ducting.

You still, however, need to be able to access the enclosed services without damaging walls, floors or ceilings. Inspection panels can give access to joints in pipework or ducting, where leaks are most likely to occur, or junction boxes, from which wiring circuits can be extended.

These can be created when the surfaces are initially fitted, or after repairs. In a floor, for example, this can simply be a loose section of chipboard or floorboard screwed to battens fitted between joists. But there are also specialist companies which can provide unobtrusive panels, including those within tiled areas.

Another way of tidying up cabling, and making it much easier to replace when necessary, is to use trunking, made from PVC, fibreglass or metal. New cabling can simply be attached to the old and pulled into position.

Lighting and power cabling, however, should last around 25 years so running it through trunking really depends on how long you plan to stay in a property. But other cables – such as ethernet, telephone and speaker cabling for sound systems – are much more likely to need earlier upgrading.

A handy way of coping with this is to use hollow skirting, dado rails or even ceiling coving or cornicing. Alternatively they can provide support for surface trunking shaped to fit in with the design.

All of which is of limited use unless a record is kept of where the services run. The most durable way is simply to mark their locations on the floor before it’s covered, or re-covered, or on loft ceiling joists. Even better, hide a wiring and/or pipework plan for the room or floor in an inspection panel.

In years to come contractors will thank you for it, and so will your wallet.

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