Access for swallows

Does anyone know what shape and dimensions a hole in a door should be for swallows to be able to fly into a shed? Previously they were able to fly in through a window but this has now been changed. I'm anxious not to put the swallows off.

Any advice on working apertures would be appreciated! Richard

  • Hi, I found this for you, if this is the size for a nest box hole, the same would  be for a door, I would have thought.

    Have a 1 ½ "diameter hole size for the entrance. -Choose a box with EASY ACCESS FOR MAINTENANCE with a door to clean the interior each year. -Drill holes underneath to evacuate water and ventilation slots. -Use screws rather than nails (if you want to move or open your box).

  • Where did you get that info from? Swallow nests are often ‘inside’, so drilling holes doesn’t sound right. Whatever the size, access would need to be larger than nest hole as the birds need to still be flying rather than entering the nest. Swallows don’t access a nest through a hole either.

  • I googled the question as asked. What size of hole in a door would you need for a swallow to get through. The poster said they had access via a window, but no longer will have, but assumed he would like them to get access via a door, not wanting to keep a door open all the time, but to get through to build a nest in his shed. From what I found, regarding a box, I assumed the same would be suitable for access via a door?

  • Thanks. That is not the species being asked about. For (barn) swallows, ideally, it needs to be a proper opening. A length of gap. I.e. like an open window. A round hole won’t work, imo. One option, could be ‘stable door’. Not sure how many valuables there are, but leaving top half open from April would work. A carpenter would be able to make a variation where top ‘half’ is about a tenth instead. 

  • Thanks, always learning. I have swallows that nest in the overhang of the front porch, my friend has an outside building, barn/stables, with a half door, which she will leave open, from when they are due to return. Again, on researching, I read, swallow and barn swallow are the same, which I assume is the birds we have nesting. Thinking now, I can see why a hole in a door would be of no use, a bigger opening would be needed. Why would thy use a nest box, from  my original quote on  searching?

  • Your search would have returned American and/or Canadian results. Tree swallows are a different species to ours, with different requirements incl nesting. UK for the cast majority of sightings, will be barn swallows so almost everyone drops 'barn' as it's an unnecessary extra. Red rumped swallows can crop up but as said, barn swallows are what we in UK know as swallows.

  • I definitely don't need a nesting hole. It is for the swallows to fly through to the ledges that they nest on, as I can't have the door open- stable doors are out as well. I have seen them somewhere but cannot for the life of me remember where- it was a surprisingly small hole considering the swallow's relatively long wingspan.

  • The format of the site isn't great, so not helping. I know you don't want a nest hole as I wrote above. Did you see the comment about a modified stable door? i.e. not a typical stable that just opens right at the top? 

  • I can't do that as the door is ledged and braced. It would literally fall to pieces. I can only cut a hole between the frame and the bracing.

  • Ultimately, where does the definition of 'hole' end and 'gap' begin? Personally, I still don't think a hole, i.e. a drilled circle, in the door will work. Swallows will need to be airborne on both sides, not like birds accessing a nestbox. As prev., there are many species of swallows. Was it a (barn) swallow that you remember seeing going through a small hole, or filming done overseas of another species? I pictured a simple softwood shed and was suggesting replacing the door. I may have pictured a different shed to what you actually have.