Getting WiFi to the Garage, Granny Flat or Back Deck

The house is fine. It is everything outside the house that is the problem.

Home offices in the garage, a studio out the back, a granny flat with a tenant, a deck where you would like to watch something. All of them sit outside the range of a router that was never asked to reach that far.

Why detached spaces are so difficult

Two things are working against you at once.

First, distance. The signal has already crossed the whole house before it gets to the back door.

Second, the buildings themselves. A garage or studio has its own external walls, and those walls block the signal from getting in just as effectively as the house walls blocked it from getting out. Colorbond and metal cladding are particularly good at it, because metal reflects the signal rather than letting it through.

A granny flat with rendered masonry walls, or a garage with a metal roller door, can be five metres from the house and still have effectively no usable signal.

What people try first

A plug-in extender near the back door. It picks up a signal that is already weak, halves the throughput, and rebroadcasts it into a wall. Occasionally this is enough for browsing. Usually it is not.

If the problem is a specific weak area rather than a completely detached building, our WiFi dead zone fixes explain the options for improving coverage without simply repeating an already weak signal.

Moving the router closer to the back of the house. This can work, but it just moves the dead zone to the front of the house instead.

Powerline adapters. These send data over the electrical wiring. They can work well, but only if both points are on the same circuit and the wiring is in good condition. In older homes and in detached buildings on a separate sub-board, results are inconsistent. Worth trying if you already own a set. Not worth planning around.

The reliable option: run a cable

The answer that actually holds up is a cable to the detached building and an access point at the far end.

Once the cable is there, the outbuilding effectively has its own strong network rather than trying to catch a weak signal through a metal wall. Whether it is a home office, a granny flat or a studio, it behaves like a proper part of the house.

Outdoor cable runs need to be done properly. That means external grade cable, protection from sun and weather, correct conduit where required, and appropriate protection where the cable enters and leaves each building. This is not the place for a cheap indoor cable stapled along a fence.

For this type of installation, professional network and data cabling provides a reliable connection between the main house and the detached space, rather than depending on WiFi to cross multiple external walls.

Cabling connected to the telecommunications network must be carried out by a registered cabler. AVsion holds ACRS Master Cabler registration A036841.

There is a second benefit worth knowing about. Once a cable reaches an outbuilding, security cameras, intercoms and AV equipment out there become straightforward too. Most people who run a cable to the garage end up using it for more than WiFi.

Outdoor areas are a different problem again

A deck, pool area or courtyard does not have walls to block the signal, but it does have distance, and standard indoor equipment is not built to sit in weather.

Outdoor rated access points exist and work well. They are designed for sun, rain and salt air, which matters near the coast where standard equipment corrodes quickly.

Worth being realistic here. Full strength coverage across an entire block is a bigger job than covering a seating area. Deciding where you actually want it to work makes the job simpler and the result better.

If the detached space and outdoor areas are part of a broader coverage problem across the property, a properly designed whole-home WiFi setup can connect multiple access points and provide consistent coverage where it is actually needed.

Things worth deciding upfront

• Is the outbuilding a permanent workspace or occasional use?
• Does a tenant need their own separate network, kept apart from yours?
• Are there cameras or an intercom out there now, or likely later?
• Is the outdoor coverage for a specific area or the whole yard?

Answering these before anyone starts saves doing the job twice. See network and data cabling for how the work is carried out.

All installation work carries a 12 month labour warranty.

Written by Yariv, Owner and Lead Installer at AVsion. 14 years installing AV, WiFi and security systems across Sydney’s eastern suburbs.

Frequently asked questions

How do I get WiFi to a granny flat or studio?

The reliable method is to run a cable from the main house to the outbuilding and install an access point there. That gives the building its own full strength network rather than relying on a weak signal passing through two sets of external walls. Wireless options exist but are inconsistent, particularly where the outbuilding has metal cladding or rendered masonry walls.

Why does my garage have no WiFi even though it is close to the house?

Distance is only part of it. The signal has already crossed the house before it reaches the back door, and the garage then has its own external walls blocking it from getting in. Metal cladding and roller doors are especially effective at reflecting WiFi signal. A building five metres from the house can have almost no usable coverage for this reason.

Do powerline adapters work for a detached building?

Sometimes, but they are unreliable to plan around. Powerline adapters send data over the electrical wiring and only perform well when both points sit on the same circuit and the wiring is in good condition. Older homes and detached buildings on a separate sub-board often give poor results. They are worth trying if you already own a set, but a cable run is the dependable solution.

Can network cable be run outside safely?

Yes, when it is done properly. Outdoor runs need external grade cable, protection from sun and weather, appropriate conduit, and correct protection where the cable enters and exits each building. Indoor cable run along a fence will fail. Cabling connected to the telecommunications network must be carried out by a registered cabler, and AVsion holds ACRS Master Cabler registration A036841.

Can I get WiFi on my deck or around the pool?

Yes, using outdoor rated access points designed to handle sun, rain and salt air. Standard indoor equipment corrodes quickly in coastal conditions and is not built for outdoor mounting. It helps to be specific about which areas you want covered, because covering a seating area is a considerably smaller job than covering an entire block.

Can a tenant in a granny flat have their own separate network?

Yes. A separate network can be configured so the granny flat has its own access and cannot see devices on the main household network. This is worth setting up from the start if the space is tenanted, both for privacy and for keeping the two households’ devices apart. It is a configuration decision, so it is easiest to raise it before the work begins.