Which size nestbox hole for which bird?
25mm - blue tit, coal tit, marsh tit
32mm - great tit, tree sparrow, pied flycatcher, house sparrow, nuthatch, lesser spotted woodpecker. 32mm entry holes can, if you wish, be reduced to 25mm using a nest box plate (R0110).
Cleaning
The box has two screws, each level with the entrance holes on the side panels of the box. Once loosened, the front panel of the box pivots open to allow access to all three chambers. Only do this for maintenance after the breeding season has finished.
RSPB nest boxes are made with thick FSC
® certified timber and will survive for many years, even without the use of preservatives.
If you do want to protect your nest box further, use a water-based preservative (preferably one that complies with standard EN71 part 3 as safe for children's toys). Such paint/preservative types are clearly marked on the container, and are available from DIY stores and hardware shops.
Preservatives should only be applied to the outside of the box. Apply in the winter, when there is a low likelihood of occupancy. This will allow time for any remaining volatile components to evaporate.
For more information about siting a nest box please see the Advice section of the main RSPB website.
Fittings/fixtures are not supplied with this nest box.