Period property: maintenance required

Don't ignore cracks in your ceilings - especially if your house is old. It could spell disaster, warns Ben West

I have always been of the persuasion that it is better to buy a cheap property at a lower price and do it up rather than buy a new or newly renovated home at an inflated price and subsequently line the already well-insulated pockets of the developer or builder selling it to me.

The downside to this is the seemingly endless renovation and refurbishment tasks that need to be carried out to bring the property up to scratch, and also the risk you take that some costly expense has been overlooked, triggering a far larger dent in your bank account than first predicted.

The Victorian south London house my wife and I bought to house our three children was in need of renovation - the principal reason why it was remotely affordable. We endured months of plaster dust routinely floating around the house, endless half-painted walls, half-finished wiring projects and all the other hallmarks of rebuilding, even sharing our kitchen with a cement-mixer at one point. It seemed that each time we removed some wallpaper, the whole wall would come down, and indeed every wall has been replastered now.

Although most of this was tedious rather than dangerous, there was one aspect of knocking the house into shape that is seldom appreciated by homeowners, and which had the potential to cause a horrendous accident.

I'm not talking about the occasion where the pane of glass fell out of the window frame because the putty had rotted away. Or the time my four-year-old son fell through the rotten floorboards. And I don't mean the other time he slipped down the stepladder standing in for a staircase. No, it was the collapsing ceilings that nearly finished us off.

Soon after I had completed decorating the sitting room, a small crack appeared in the ceiling, possibly caused by slamming doors, the children jumping around upstairs or perhaps the vibrations from the lorries and buses that drive past our house each day. Maybe it was the result of a small flood in the bathroom above some months ago, thermal expansion stressing the ceiling or overloading the room above in the past.

My wife said that we should have the ceiling looked at, but I wasn't at all keen. It had taken months to finish the room, to remove the wallpaper, re-line the room, repair the fireplace, restore the cornicing and woodwork and apply the paint, and the last thing I wanted to do was go back over what I considered a completed job. Anyway, I had far more important things to do, like listen to my CDs and go to the pub.

Over a few weeks the crack in the ceiling got a bit bigger, but still it all looked very benign. It didn't sag at all, and it looked just like any ceiling you'd see again and again in older houses.

Then one day I heard the most incredible loud bang, which I can only describe as being the sound of around 10 full bookcases falling down. Sure enough, the whole ceiling had crashed to the floor, instantly transforming the room into what looked like a war zone, a mass of rubble and swirling grey dust.

The most chilling thing was that the children had been in the room only moments before. Being a Victorian house, the ceiling was made of lath and plaster and was therefore several inches thick and similar to a whole raft of bricks coming down. What would have happened had the children been in the room at the time does not bear thinking about.

Not being a great one to learn a lesson, I was forced to eat humble pie a year later, when exactly the same thing happened in another room after a door was slammed. In my defence I can testify that the cracked ceiling was significantly smaller. I will always remember my wife's face after she had again shown me the ceiling, I dismissed it and went to the shops, only to return to a second bomb site. I remember her bemused expression as she uttered words not dissimilar to "I told you so".

Roy Ilott, a chartered buildings surveyor, says: "With older houses you can go into the roof space and move the insulation to see if the lath and plaster has lost its bond. But it is almost impossible to find out the true condition of the ceiling on the floors below. You can press gently on a ceiling, and if it moves up and down you know it is 'live', meaning that it is in danger of coming down.

"You can restore the bond to the ceiling just between the laths but this is labour-intensive and so many people just nail in plasterboard. But if the nails are not large enough you have a false sense of security as the ceiling could still come down, but will now be even heavier. These problems usually occur in older houses, often with ornamental cornices and roses which people don't want to lose. But if the ceiling is live it should be replaced.

"People underestimate cracks in a ceiling. They put lining paper up and hope that will keep it up, but there is a lot of weight up there. Any movement in the ceiling, rather than the length of the crack, is the thing to watch for."

Ben West is the author of 'Buying a Home' (Virgin, £8.99) and 'Buying a Property Abroad' (Cadogan, £12.99).