Nesting Boxes

Bird Nesting Box FAQs

Nesting boxes are a great way to help our native songbirds. To help you with choosing and installing a bird box, here are some answers to some of your FAQs.

Where to put bird boxes

The best place to put a nest box is:

• Away from other nest boxes
• Not too close to your bird feeders
• Sheltered from prevailing wind and weather
• A spot shaded from bright sunshine
• At least 1m off the ground, up to 3m
• A location inaccessible to predators like cats.

A tree is a great option and the closest to birds’ own natural habitat, but if you don’t have any trees a wall will do fine.

When installing your nesting box, make sure it’s aligned vertically or even angled so that the entrance is tilted slightly downwards to stop any rainwater from getting in. To avoid unsightly rust streaks, use galvanised or stainless steel screws, especially if you’re attaching the box to your house wall. Wherever you decide to attach your nesting box, it’s vital to ensure nothing obscures the entrance; birds require a clear flight path to their front doors.

For more useful advice read our guide on how to put up a nest box here.

How do birds claim a nesting box?

Songbirds are prospecting for a nesting site from around January and February onwards, and competition is fierce. To claim a nest box, you might see a male tit making a display of pecking around the hole. A behaviour which females engage in as well, often pecking away at the interior of the box too. Another way birds stake a claim on a nestbox is to leave items inside it or use mud to adapt the entrance to fit them exactly.

When to clean out bird nesting boxes

The best time to clean out your bird box is when the inhabitants have deserted it. Bear in mind that birds may use your boxes outside of the breeding season, often packing together into a box to keep warm during cold winter weather. For this reason, from September to the end of December is the best time for cleaning.

To clean a birdhouse, remove the front, empty the contents and use boiling water to scald the wood of any infections or parasites. Chemical cleaners are not advised because they may leave smells which will deter future residents from setting up home.

What size hole is needed for a bird box?

If they can get into a box, bigger birds will sometimes evict smaller ones. So it’s important to consider the birds you would like to encourage when choosing a box, for example:

• 25mm hole – tits
• 32mm hole – sparrows, nuthatches and pied flycatchers
• 45mm hole – starlings
• Open front – robins, wrens, blackbirds, and song thrushes

To help prevent birds from bullying one another from your nest boxes, avoid mounting a perch at the entrance—the inhabitants won’t need it anyway.