Questions about Bat Houses

“Where is the best place to put a bat house?”

Bats like to choose from a variety of roosts as the seasons change – they are mammals which need to avoid losing energy unnecessarily to thermo-regulation. Position your bat homes somewhere between 3m and 6m (10′ to 20′) off the ground and in various aspects, South and East facing especially. Select locations furthest from trees and other vantage points that could be used by potential predators. You will also want to avoid siting bat homes above windows and doors. Bats feed on insects and also need water to drink, so these are also important considerations.

“Will bats hibernate in bat houses?”

Yes they will. During the winter months, bats will find a hibernation roost and huddle together as they largely shut down. Their body temperatures can fall dramatically – a 2012 study in the Journal of Mammalogy (Oxford University Press) revealed that the skin temperatures of hibernating Big Brown Bats in the US fluctuated from over 35 °C to less than 5 °C. Bats actually prefer winter roosts with a relatively constant temperature however and bat homes which are integral to buildings are useful for this purpose.

Why are bat houses important?”

Bats do some vital work in our ecosystem, from eating insects and bugs (the UK’s bat species eat nothing larger), thereby offering crops and gardeners some assistance, to pollinating plants. In fact, many plants which bees tend to avoid will be attractive to bats for nectar. Bat guano is a terrific fertiliser too, so bats are worth cultivating. Originally bats would have lived in trees and other natural shelters, however more recently they have evolved to live in older houses, churches (as in ‘bats in the belfry’), barns and other farm buildings. Modern construction materials and methods offer fewer (if any) opportunities for bats to roost, so it’s really important to make special provision in new developments in the right locations.

“How do bat houses work?”

Simply by providing roosting sites that offer the right range of temperature and where bats feel safe from predators. In the UK, seagulls for example are rather partial to bats and will sometimes take up a position outside a bat roost (if they can), ready for a meal as the bats leave. A well made bat house will contain rough surfaces as bats go to sleep hanging, using their hooked claws on their wings and toes to get a foothold.

“How many bat houses do I need?”

While a single bat house is better than none, bats do like to be able to select from a variety of sites, depending on their temperature needs. In general they like cooler houses in which to hibernate and warmer zones in summer. On a given building, three bat houses is a good aim; if possible, these locations should be sunlit for at least part of the day,

“How high should bat houses be?”

Anywhere between around 3 and 6 metres (10 to 20 feet) above ground level is fine. Bats like to feel safe from ground based predators such as cats.

“When should I install bat houses?”

It’s fine to fit bat houses at any time of the year, however it makes most sense to complete your installation by early Springtime, as it will stand a chance of attracting bats emerging from their local hibernation, also other species who have wintered abroad.

“What do bat houses look like?”

Externally, you are most likely to see either a slot in a wall, or a rectangular box with a narrow entrance aperture at the bottom. Click here to see bat houses made by Bird Brick Houses – these are designed to be integral to buildings, so all that is seen externally is the narrow slot in the brick / stone / render.

“What direction should bat houses face?”

In the UK, bat houses should generally face East, South or West, and positioned such that they are in sunlight for several hours a day to keep the roosting area warm.

“What attracts bats to bat houses?”

A bat house that ticks the following boxes has a good chance of being occupied: –

  • The right temperature – ideally site several boxes on a given building with a variety of aspects so that the bats can select how warm or cool they want to be.
  • Safe from predation – bat houses are best positioned well away from trees, bushes, lamp posts etc which offer a convenient launch site for bat predators e.g. seagulls, hawks and owls.
  • The right internal surface – well designed bat houses come with rough interiors, allowing the bats to hang while they sleep.

Questions about Bird Houses

“How do birdhouses work?”

By providing an environment in which the birds feel warm and safe, that’s large enough for them to move around and raise a family, and by using an entrance aperture which is only just large enough for the target species to use, thereby eliminating use by larger (possibly predatory) birds e.g. magpies.

“Are bird houses good for the environment?”

Many of the UK’s garden birds are struggling to maintain numbers, house sparrows being an obvious species that has suffered a serious decline in recent times. Providing bird houses is hugely important for giving such birds the best chance of rearing their young and surviving the winter in as safe an environment as possible. Another relatively little known effect of encouraging songbirds is the beneficial effect on our own (human) wellbeing, despite many studies over the years which have proven a link between audible bird song and good mental health. One example is ‘Urban Mind: Using Smartphone Technologies to Investigate the impact of Nature on Mental Wellbeing in Real Time’, published in BioScience 10th January 2018.

“Where do I put bird houses / nesting boxes?”

In the UK, traditional wooden bird nesting boxes which are attached to trees or buildings should ideally face East or North, to protect occupants from the prevailing wind and rain, also from strong direct sunlight. Integral bird boxes, such as those manufactured by Bird Brick Houses are less exposed to the elements and it’s more a case of how high off the ground should the box be sited in order to provide protection from predators. Integral nesting boxes have the advantage of being sited in a sheer ‘cliff face’, making life more difficult for the likes of magpies to threaten fledglings. As a rule of thumb, 3 metres (10 feet) from ground level is a sensible minimum, although for more species specific guidance, click here.

“What bird houses attract which birds?”

The British Trust for Ornithology (BTO) has an excellent guide showing which species will tend to use various bird house shapes and sizes. In general, birds are looking for a dry, reasonably warm dwelling where they feel safe from predators – the latter point being the key in determining which species will use a particular house. A small blue tit for example will not want to use a house with an entrance aperture a larger bird could enter, given the sometimes malign intent of the likes of magpies and cuckoos.

“When do I clean bird houses?”

Some species (notably the tit family) clean out their own nesting area and our experience at Bird Brick Houses suggests that birds will re-use untended boxes year on year. If you decide to clean out your bird house, note that Bird Protection Law allows this only between 1 September and 31 January. Even in the Autumn, some species may still be producing second or third broods, or the house may be being used through the Winter as a roost, so always make certain the box is no longer being used.

“Can I get bird houses for owls?”

Yes, these are widely available and vary according to the species of owl. Click here to take you to the relevant Bird Brick House website page, where you will discover the various designs for several of the UK’s owl species. Tawny owls are the only owl to use the ‘Twit Twoo’ call. Little Owls like to enter their nesting house through a short tunnel, so these houses are a little more sophisticated. Barn Owls like a large nesting area with a perching platform. Owls are too large for the kind of integral nesting boxes used by the likes of swifts, sparrows and the tit family.

Questions about Swift Houses

“When do swifts nest in the UK?”

Swifts arrive in early May and return to their winter homeland from around mid August. They will generally have completed nest building the previous year and will return to the exact same site the following summer. Integral swift nesting boxes manufactured by Bird Brick Houses include a nesting cup which saves the breeding pair a whole season of nest building.

“Where do swifts nest?”

Swifts will look for nesting sites which give them a helping hand, since they don’t land on the ground and (incredibly) collect nesting material in flight. All sorts of light debris is carried into the air on summer thermals; swifts are amazing aerial acrobats and can, for example,  grab floating pieces of straw to use in the nest building. The nests will be relatively high, so that the birds can drop into flight, rather than taking off from the ground (they can’t). The helping hand typically comes literally in the shape of nooks and crannies of older buildings, where they often favour nest building up under the eaves. Should a development or improvement disturb an existing swift nest, it should, if at all possible, be re-sited in exactly the same place as the birds will want to return to it year after year.

How do I attract birds to a nest box?”

Swifts are more likely to use an appropriate nesting site if a recording of their calls is played. A CD is available from the Bird Brick Houses shop which should be played from a speaker as close as possible to the site. For further options and information it’s worth checking out the Swift Conservation website.