Renovation can reveal much
After renovation work is under way you can discover some nasty surprises.
Here is a look at common problems discovered behind walls, ceilings and under floors.
Depending on the age of your house, it’s when you start removing wallboards and other sections of the house that you discover the true state of things, for example:
Wiring – people commonly discover they need to rewire because the electrical wiring and fittings have become unsafe.
This is particularly true for wiring in black or white rubberlike sheathing (pre-1960 houses), timber conduit (pre-1950 houses) or steel conduit (pre-1940 houses).
Plumbing – corrosion of water pipes, particularly old galvanised pipes, can sometimes be so bad that the whole house needs new plumbing, hot water reticulation is likely to be low pressure, or disconnected waste pipes may be emptying into the subfloor.
Carpentry – a rotten weatherboard can reveal rotten framing when the board is removed, floors out of level, and serious borer.
Corrosion – under flashings and under the bottom edge of the laps of galvanised steel roofing.
Glazing – in older homes it is often thin, can break easily and is a safety hazard.
Asbestos, which could present a safety risk, may be discovered in some materials such as roofing, sprayed ceilings, cement sheeting, and some floor coverings.
Working with treated timber
When working with treated timber, there is a risk of inhalation of noxious fumes and dust.
Guidelines have been put together for people working with light organic solvent preservatives (LOSP) or copper, chromium and arsenic (CCA) treated timber.
These guidelines can be found at www.nztif.co.nz.
The guidelines recommend waiting for the preservatives to dry off before using the treated timber, but if this is not an option, wear protective goggles and use a respirator when cutting or sanding treated timber.
You should also wash your clothes separately from other household clothing and wash your hands before eating, drinking or smoking.
Any off-cuts should be disposed of in a proper landfill.
Working with asbestos
Some older homes built before 1983 may have been built with materials that contain asbestos.
For example, sprayed ceilings, cement sheeting, some types of floor coverings and some roof materials.
Breathing in dust and fibres containing asbestos can cause asbestos-related diseases such as mesothelioma (a cancer of the chest lining) and pleural diseases (including fluid on the lungs, and asbestosis, which is scarring of the lungs).
These diseases are crippling, very painful and usually fatal.
There are no known cures for asbestos-related diseases.
However, provided the materials containing asbestos are in good condition and have a good coat of paint, there should be no health risk.
If your renovations involve removing or sanding materials that you suspect could contain asbestos, or if you are unsure what the materials are made of, contact the health protection officer of your local District Health Board for advice on identifying and managing this material.
Asbestos materials should only be removed or handled by a contractor experienced in this type of work. Look under ‘‘Asbestos’’ in the Yellow Pages.
Other renovation issues include unstable brick chimneys, lack of sub-floor ventilation, no insulation in the walls or ceiling, floor and framing too close to the ground, foundation settlement, and insufficient lateral support (bracing) in the sub-floor structure.
It can be difficult to budget a set figure because so much of the work is unseen before you start.
Your alterations may have to go
on hold due to urgent repair work.
A note about glazing
If you are replacing glass, it must be replaced with glass that complies with the Building Code.
Acceptable Solution F2/AS1 requires glazing that people may fall against to comply with NZS 4223 Code of Practice for Glazing in Buildings.
skilled tradesperson should be knowledgeable about Building Code requirements.
But when you are renovating make sure that in areas where slips are more likely – such as in bathrooms and kitchen, or where windows are close to the floor or at the end of stairwells – that the right grade of glass is used.
The New Zealand Standard 4223:1999 gives minimum requirements for glazing in buildings where people risk injury by falling into the glass.
There is a range of glasses you can choose from depending on what you want to achieve, including thermal insulation, for example, double glazing or tinted glass.
Things to consider with glass include noise reduction, safety in areas of impact risk – for example, safety glass – and privacy and fade protection – for example, tinted glass.
Some glasses will do all of these things, for example, double glazing, which is made using two sheets of glass with an air cavity between, to reduce heat loss and condensation. The advantage of double glazing is that you can have more window space without heat loss, and the house is cooler in summer. It can be tinted and toughened and reduces noise from outside.
Other points to note about different types of glass:
Insulating glass is available that has an insulating coating;
Glass designed specially to reduce noise is made from two sheets of glass bonded together;
Safety glass should be used in those areas where falls are likely, for example, ranch sliders, shower enclosures, or around stairs.
Glass specially strengthened to deter break-ins is available. It is resistant to breaking if hit with objects such as a hammer.
Self-cleaning glass is available. It is useful for external windows that are hard to reach.
Decorative glass is available for special effect, such as frosted, leadlight, coloured or textured.
There are also glass bricks for walls, partitions and special effect.
Before you decide on which type of glass should go where, find out what is available and talk with your designer to decide the best type of glass for each area of the house.
Keep your mind open to interesting and innovative ways to make your new home attractive and energy-efficient.