Tips & Tricks

Old Houses Move

This is Harry. G’day. I’m Harry. Harry lives in an old house. Yeah, it’s pretty old. Ever since it was built Harry’s house moved up and down with the seasons. My house is moving.

Back when Harry’s house was built, people understood that houses move and so they did some things to account for the effects of that movement.

“We paint our house every few years.”

“We have tongue and groove walls so I can’t tell there’s movement.”

“Our house has some hairline cracks but that’s okay, we know it’s not the Taj Mahal.”

They weren’t too concerned about a few cracks because they knew the house was built using strong materials that could accommodate some movement.

“My living room has asbestos cement walls. They’re very strong.”

“My builder uses fibro in the bathroom and tongue and groove in the living room. It’s just gorgeous.”

But eventually, the older house got sold to new owners.

“It’s time for me to move into a retirement village. See ya.”

And new owners moved in with new ideas.

“My wife wants to be able to watch the kids in the lounge room from the kitchen so we’re going to knock out this wall and put in a beam.”

“The house was looking pretty dated so we removed the asbestos cement walls and re-clad them with beautiful smooth plasterboard don’t you just love this color? “

And the old house kept on moving.

Now if anyone had asked Harry he would have said,

“This house always moved with the seasons. You better get used to it.”

But the new owners expected their house to perform like a new house.

“We can’t afford to repaint our┬áhouse every couple of years.”

And the old house kept on moving.

One day, there was an almighty storm. The skies opened. Rain came bucketing down. Some houses even flooded.

“In Graceville Gaynor and Mike only bought their home three years ago I mean it’s our first home together you know it’s our yeah it’s you know it’s it’s our little sanctuary.”

After the storm things slowly started to return to normal.

People washed the mud out of their homes and dried out their belongings. Some homes were rebuilt. Some just removed their wall cladding to allow the walls to dry up.

Some houses seemed okay at the time but people got nervous.

“There are cracks in my walls. I’m worried my house is collapsing.”

“Ever since the flood, my house has moved. It must be because of the flood.”

“Please help! Our house is falling down.”

And the old house just kept on moving.

So what can be done about older houses that keep moving? Can they just be patched and painted after a storm or do they need to be strengthened in a way so that they never move again?

As a homeowner or a builder or an insurance company we have three options for you.

The movement in these older houses will continue each year – year after year – so option one is to tell the owners what to expect. Just because the walls are being clad in shiny new plasterboard doesn’t mean the house will suddenly stop moving.

The need for a patch and paint doesn’t go away when you buy an older house.

Owners need to be aware that cracks up to five millimeters wide are okay. They’re to be expected and the walls just need some love.

Older houses also need some maintenance like engaging a builder or a handyman to re-level the house every now and then with packers on top of the stumps or to replace some of the stumps with adjustable steel stumps so they can be leveled up or down a lot more easily.

Option Two is to try and remove some of the issues that we now know cause young and old houses to move each season.

  • Improve site drainage so that stormwater doesn’t sit beside or under a house for a long time.
  • Fix gutters and downpipes so they don’t overflow onto the ground beside the house.
  • Don’t plant potentially large trees right beside a house because we know that tree roots affect the performance of a house.
  • Fix broken and leaking stormwater and sewer pipes promptly.
  • Fix leaking taps and fill in dog holes so that water doesn’t sit near the footings.

Option Three is to upgrade the footing system to a more modern footing system to help protect the building from seasonal ground movement.

All of the existing stumps and footings need to be demolished and replaced with a grid of strong concrete beams under the house.

Option Three is effectively a major footing system upgrade.

This is very expensive and difficult to do and the work still doesn’t guarantee that the house won’t be affected by seasonal ground moisture changes and movement.

So the option you choose depends on your budget and the homeowner’s acceptance that older houses do move.

Some people just aren’t ready to accept that their house will move and crack each season so maybe they aren’t the best owners of an older home.

The danger with repairing an older home after a storm event is the home will continue to move and then the blame for that movement might be accidentally attributed to the builder that did the repairs.

That’s no fun for anybody.

So, what level of movement is okay in an older house and when should a homeowner actually start to worry.

  • A good rule of thumb is that a few cracks up to five millimeters wide are okay.
  • One or more cracks wider than five millimeters along with some sticking doors or windows means that you probably should get your house checked to see what you can do to improve the performance of the footings.
  • One or more cracks wider than 15 millimeters wide means that you probably need a structural engineer and a builder to check what is going on with your house – perhaps there is some termite damage or water damage in the building that needs to be repaired.

Unless something serious around your house changes like soil gets washed away or a slope subsides, most older houses will continue to stand up strong and proud with only some minor cracking each season.

So long as you’re a homeowner that can tolerate doing some maintenance around your house like getting cracks patched and painted or getting your stumps adjusted then an older house will continue to perform just fine for you.

If you’re less willing to accept cracking in your house then perhaps an older-style house isn’t the right kind of house for you.

I’m Matt Cornell from Cornell Engineers.