How to build a nest box yourself? What properties should it have? We share tips on building and hanging the perfect bird box.
Birds are certainly among the most popular garden animals, because their beautiful singing not only flatters our ears, but they are also exciting to watch. To attract birds to the garden, many people put up nesting boxes in which the feathered animals can raise their offspring. Not only is watching the young birds a great event - building a nesting box yourself is also fun and makes an important contribution to bird protection. We will now tell you why birds need nesting boxes and what you need to pay attention to when building nesting boxes.
Why do birds need nest boxes?
A common question many ask: do birds need nest boxes? After all, they build their own nest in nature. The reason for the need for nesting boxes actually lies with us humans: Many birds only nest in dead wood, natural caves and in suitable wall niches - but all these places have become a rarity in modern landscapes created by humans. Nesting aids are an absolutely sensible alternative so that birds can still raise their offspring in a suitable place.
But nesting boxes are not only useful for birds during breeding. Especially on cold winter nights, many of them are happy to have sheltered accommodation. Since birds have to maintain a constant body temperature of 39 to 42 °C, a night without adequate weather protection can be fatal to them. In fact, some bird species - such as the house sparrow - are known to set up a veritable winter nest in the nest box. But insects, squirrels and even bats also like to use nesting boxes as a retreat in winter.
Tip: When deciding to build a nesting box, the question arises as to which birds can actually use it. We provide the answer to the question “which bird builds which nest?”.
Build a nest box yourself: you should pay attention to this
There are a few things to keep in mind when building a nest box if you really want the residents to feel comfortable. It starts when you put together the material to build the nesting box yourself: wood-concrete, terracotta or the classic wood are suitable. Untreated oak, robinia or larch boards are particularly suitable for building nesting boxes, as they are very weather-resistant. Plywood and chipboard, on the other hand, do not withstand wet or cold well and are therefore hardly suitable. You should also stay away from plastic: Since it is not breathable, moisture collects inside plastic bird nest boxes, which in the worst case can lead to mold on the nest. There is also a lack of the necessary insulation, which can lead to strong temperature fluctuations.
If you want to customize your nesting box, you can also paint your bird house with colors and glazes. However, it is important to ensure that the colors used meet the safety requirements for children's toys and are ideally biodegradable. Linseed oil is suitable, for example, as a glaze against moisture and is also absolutely harmless for birds. Bright colors also make the nesting box more visible to predators. It is therefore advisable to use earthy, natural colors such as greens and browns when painting.
You should also pay attention to the right dimensions when building the nest box: the bottom of the nest box should be at least 12 x 12 centimeters in order to offer enough space for the brood. Four holes with a diameter of five millimeters in the bottom also ensure better ventilation and make it easier to dry the nest. In addition, the lower edge of the entrance hole should be at least 17 centimeters above the bottom of the box and the box should have a sufficiently large roof overhang. This protects the birds from predators trying to get to the eggs.
Tip: A perch actually helps dangerous predators get into the bird box, so you should never attach one.
This is what the perfect nesting box looks like
As far as the exact appearance of the box is concerned, it is important to orientate yourself on the respective bird species, because a tit box needs different conditions than a swift nest box. The typical Starenkasten or alsoTit box with its rectangular shape and round entrance hole is used by numerous species of birds. Which species moves into the nest box depends heavily on the size of the entrance hole: each bird species prefers a different size here. We have compiled the entrance hole sizes for the most common bird species here for you:
| 26 - 28 mm | Most species of tit (blue tit, coal tit, marsh tit, crested tit, meadow tit) |
| 32mm | Great Tit, Tree Sparrow |
| 32 - 34 mm | Pied Flycatcher, House Sparrow |
| 32 - 45 mm | Nuthatch |
| 45mm | Star |
| 48 mm high, 32 mm wide (oval) | Redstart |
In addition to the typical tit nest boxes, there are also other types of nest boxes that are used by various bird species. Some free breeders and species that depend on breeding niches are happy about a breeding aid in the "semi-cave format". This nesting box for robins, spotted flycatchers, wagtails or wrens does not have an entrance hole, but has a half-open front. Swifts also have very special requirements when it comes to their nest boxes: These should be flat rather than upright and have an oval hole (6.4 x 3.2 centimetres).
Hanging up and caring for nest boxes for birds correctly
If you have built a nesting box yourself, it is now important to attach it to a suitable location. In fact, this is decisive for whether the incubator is accepted by birds. If the location is unfortunate, even the best nesting box will not be used. Ideally, the nesting aid should be placed about two to three meters above the ground. The entrance hole should neither point to the weather side (to the west) nor should it be in the shade or in the blazing sun. Orientation to the southeast or east has therefore proven itself. Suitable locations for nesting boxes are weather-protected places on a tree, post or even a house wall. Especially in the case of nesting boxes for robins or other semi-cave breeders, care must be taken to ensure that the area is as inaccessible as possible for martens or cats.
The self-made nesting box can then be attached to the appropriate place with rustproof nails or screws so that it is slightly forwardtilts. For trees, fixed wire brackets are ideal for attachment - these do not damage the tree and can be gently removed again if necessary. There should be a distance of at least ten meters between nesting aids of the same kind so that there are no neighborhood disputes. The only exception: colony breeders prefer to stay together in groups. Star boxes, nesting boxes for swallows or sparrows are therefore welcome to be hung up in the immediate vicinity.
If the birds are fed regularly, there should also be enough distance to the feeding place: On the one hand, such places are often too restless for the brood, since many different birds fly to them. On the other hand, a feeding place always attracts the attention of predators, so that the nesting aid is discovered more quickly. Incidentally, the perfect time to hang up a bird house is autumn: the animals can use the nesting aid as protection in winter and get used to the construction before the start of the breeding season. After hanging, it is best to leave the nest box alone as too much agitation will deter the birds.
Note: However, given enough spacing, a bird feeder is a perfect addition to a bird-friendly garden. With our Plantura all-season food, for example, you can support numerous garden birds both in summer and in winter with lots of energy and he althy nutrients.
The nesting box only has to be cleaned once a year to get rid of vermin and dirt. The best time to clean the nest box is in late summer, after the breeding season is over. During cleaning, old nesting material is removed and coarse dirt is brushed out of the nesting aid. To learn how to do this, see our article on cleaning nest boxes.
Would you like to do more for the birds in your garden? You can find out how to make your own birdseed and which native shrubs are particularly suitable for birds in our articles “Make your own bird seed: instructions & tips” and “Native shrubs for birds”.
And if you want to know how to turn your garden into a real paradise for birds, be sure to check out our article Bird-Friendly Garden: The 10 Best Plants for Songbirds.