Rainwater Tanks and Gutter Guard: What It Can and Can't Do

You can manage without it, but it helps. Everything that lands on your roof washes into the gutter and then on toward the tank. Gutter guard on your home keeps leaves and twigs out of the gutter, so less of that ends up in the water. It isn't a filter, and it doesn't replace one.

Queensland Health's tank guide (opens in a new tab) says upkeep is needed to keep the water quality good and stop mosquitoes breeding. The roof and gutters are on its list. Every six months, it says to check them for built-up leaf and other plant matter, remove all of it, and prune back branches hanging over the roof.

Mesh helps with that. Leaves that land on it can blow or wash off, instead of packing into the gutter. You'd still do the six-monthly check. You just won't be up the ladder every few months scooping out leaves.

Still weighing it up? Read the pros and cons of gutter guard first.

Through a downpipe. Rain runs off the roof into the gutter, down the downpipe and into the tank. Brisbane City Council suggests (opens in a new tab) putting the tank where your downpipes already are, so all the rain from that part of the roof goes in. Fitting the tank isn't a DIY job.

The council is clear on that. You can't install a rainwater tank yourself, it says. If the tank water connects to your toilet or the cold tap for your washing machine, a licensed plumber is needed.

A couple of things protect the water on the way down. A first flush diverter stops the first flow off the roof from going into the tank. Mosquito-proof screens should cover every opening into the tank, the overflow included. In some setups, the screen is built into a rain head or the first flush device.

Roof, gutter, downpipe, tank. Gutter guard sits right at the start of that path, on the gutter itself. It's fitted over the gutters you already have, after a free clean, and the rain runs through the mesh to the downpipes. Here's how we install it, from the free quote to the written guarantees.

A first flush diverter stops the first flow of water off your roof from going into the tank. Brisbane City Council recommends fitting one. It's part of the tank plumbing, so talk to a plumber or your tank supplier about it. Gutter guard sits higher up, on the gutter, and does a different job.

The diverter needs looking after too. Queensland Health says to check and clean it every three months. The council says to open it and clean it out after rain.

Then there are the tank screens. In Queensland, all new tanks must have mosquito-proof screens, flap valves or both on every opening, overflows included. Queensland Health says the screens must be brass, copper, aluminium or stainless steel gauze, with a mesh size of 1 mm or less.

That's finer than the mesh we fit. Our expanded mesh has 3 mm holes and our woven mesh has 2 mm holes, sized to stop leaves while the rain runs through. So our gutter guard can't stand in for a tank screen. If you fit it, the tank still needs its screens.

They can, wherever a gutter holds water. The Queensland Government lists gutters among the places around a home where mosquitoes can breed, and its advice is to clean gutters regularly (opens in a new tab) to stop it. Brisbane City Council's tank advice (opens in a new tab) says to put in guttering that stops water pooling. A blocked gutter holds water. A clear one drains.

Leaves are usually what does the blocking. They bed down in the gutter and knit into a mat, and the mat holds water. Mesh keeps the leaves out, so the rain can drain away to the downpipe.

If a clean gutter still holds water, it may have lost its fall (its slope) or started to sag. Mesh won't fix that. We check the fall before any mesh goes on.

Tanks need watching too. Queensland Health says a tank that isn't looked after can become a mosquito breeding site, and you can be fined on the spot for not keeping yours mosquito-proof. Brisbane City Council's mosquito fact sheet (opens in a new tab) says a gap the size of a matchstick head is enough to let them in. Check the screens and flap valves for rips and holes every six months, and fix any damage straight away.

They count too. Shed gutters are often the ones nobody clears, and they're often the ones feeding the tank. If a shed fills your tank, get it looked at in the same quote. We fit mesh to sheds as well as houses, and doing both on one visit costs less than two trips out.

On acreage, the sheds and carports can make up most of the gutter on the block. Any roof that feeds the tank needs the same six-monthly check as the house.

Yes, if the gutter under it can carry the water. That's the same test as for any gutter. Our mesh stops leaves and lets the rain through to the downpipes. Water that reaches the downpipe can reach the tank. Water that spills over the edge of the gutter never gets there.

Summer storms can dump heavy rain in minutes across Brisbane, the Sunshine Coast and the Gold Coast. A gutter packed with leaves has nowhere to put that water, so it goes over the edge. On a tank home, that's water you wanted to keep.

Steep roofs send water to the gutter fast, and no mesh makes a gutter carry more water than it was built for. In a big enough downpour, any gutter can spill, guard or not. That's why we check gutter fall and downpipe capacity during the free clean before an install. The whole path has to drain, from the mesh to the downpipe.

Our guide on how gutter guard copes in heavy rain goes into the rest.

If leaves and grit have been getting into the tank, a clean before storm season is a good first step. We clear the leaves, twigs and sludge out of your gutters, then check that water runs along each gutter and out the downpipe. You don't need gutter guard to book one.

Ask us to clean the gutters and we'll give you a free quote. We clean gutters across Brisbane, the Sunshine Coast and the Gold Coast.

While you're at it, check the rest of the path. Queensland Health puts the first flush diverter on a three-month check and the tank screens on a six-month one.