Friday 30 November 2018

Grade I Swift bricks

Thank you to Peta Sams for sending this story

Built in 1797, the first iron framed building in the world, Shrewsbury Flax Mill was a very successful and profitable producer of thread until the middle of the 19th century. In 1897 the building was adapted for use as a maltings for the brewing industry and it was at this time that vents were put into the walls to help provide adequate air flow for the malting of barley. The maltings closed in 1934 but was used again for malt production between 1948 and 1987 when the site finally closed. It was during this latter phase of its use as a maltings that the inside of the vents was sealed off - between 1950 and 1980.

The innovative construction of this building paved the way for the skyscrapers of our modern world and it is recognised as one of the most important buildings from the industrial revolution. Hence its classification as a Grade 1 listed building and the current involvement by Historic England to bring the building back into a good state and see it used again.

What’s this got to do with Swifts?

Well, the closing of the vents just on the inside, together with the fortuitous wide spacing of the wooden slats on the external face of the vents, meant that around 25 Swift bricks had been created sometime between 1950 to 1980. We have no idea when the birds spotted this potential but in 1999, when Brian Martin was asked to survey the site, at least 11 pairs were observed using the vents on the west side of the Main Mill and on both the north and south sides of the adjoining Cross Mill.

Main Mill scaffolded from 2007-2018
In 2007, to prevent the collapse of the building, extensive scaffolding was erected on the Main Mill building which effectively prevented access to nest sites.

However, when Shrewsbury Swift Group surveyed the site in 2015, ten vents on the Cross Mill were seen to be in use by Swifts – which was very good news. The group have surveyed the site annually and it is good to see that the number of Swifts there is pretty stable, with up to 14 vents on the Cross Mill being used by Swifts in the last two years.

In spring 2017 more than 20 Swift boxes were put up on an adjacent building on the site in mitigation and although the birds have investigated them, they were not observed being used for nesting.

Section of the Main Mill after scaffolding
removed in 2018. There are 15 potential nest
sites here in the renovated vents.
Much effort to secure the significant funding needed for this project finally allowed work to restore the Main Mill to start in 2017 and after 11 years(!) the scaffolding has, in just the last month, been taken down.

Shrewsbury Swift Group, together with Brian Martin who has retained a very keen interest in the site since the initial survey all those years ago, visited the site very recently and were pleased to see, in addition to the 13 active nest sites seen in 2018 on the Cross Mill, there are a further 15 vents available for Swifts on the Main Mill. These have been lightly restored by Historic England and the original wood from around 1897 is in good condition and has been retained. The significant gap over the top slat has been kept.

2019 is going to be an exciting year to see if the Swifts find and use the newly available nest sites on the Main Mill that they have not been able to access for so long. We look forward to the colony growing and hope to be able to tell visitors to the Flaxmill Maltings about Swifts and how they have hung on here during all the years of uncertainty and more recently during the building works. Could these be the first ever internal Swift bricks? – and Grade 1 listed at that!

North face of Cross Mill in 2015 showing the vents
used by Swifts.

We would like to thank Historic England and especially Gabriella Smith and Nick Hill who, despite having a very serious conservation project on their hands to rescue the whole site, have been willing to let Swift group members on site and  have shown much interest themselves in the use of these Grade 1 Swift boxes by the Swifts each summer.

We have made an informed guess at what these nest spaces might be like on the inside in this model. The swifts enter and leave through the gap at the top.

Tuesday 20 November 2018

Two triangles on modern gables

We like gables because they are often the highest point that you can install a Swift box on a house, Triangular colony boxes always look nice, fitting in with the house architecture, and Swifts seem to like them.

We have recently installed 2 triangles on houses in Milton and Worlington. One has a roof slope of 9:12 and the other a slope of 12:9. One house has narrow eaves and the other broad eaves. The first one needed a roof fashioned out of shingles made from feather-boards. The second is well protected under the eaves. Neither faces south, but they are both painted white, to match the paintwork on the house.

9:12 triangle in Milton
UPDATE 2020 - 2 pairs of Swifts have moved into this triangle
12:9 triangle in Worlington


Wednesday 26 September 2018

Internal Swift nest boxes at the Hospital of St Cross, Winchester

Thanks are due to Andy Broadhurst of Hampshire Swifts for forwarding this story written by Catherine Gale, a great example of what to do in an empty roof space with open eaves.

The Hospital of St Cross is thought to be one of England’s oldest charitable institutions and has been described by Simon Jenkins as ‘England’s most perfect almshouse’. The Order of the Hospital of St Cross was founded by Bishop Henry of Blois in around 1132 to support 13 poor men. In 1445, Cardinal Henry Beaufort founded the Order of Noble Poverty, adding the Almshouse to the existing hospital buildings. The appearance of the Hospital has changed little since then.

External view
Several of the Brothers who live at the Hospital remember summers when large numbers of swifts could be seen and heard over the Hospital, but they report that there are now far fewer than there used to be. With the enthusiastic support of Catriona Morley, the Clerk of the Trustees at the Hospital of St Cross, Hampshire Swifts have just completed the first stage of a project that aims to increase the swift population at the Hospital.

In May this year, Tim Norriss and Catharine Gale of Hampshire Swifts were invited with Tim Walker to visit the Hospital and Catriona showed them the huge loft that runs the length of the Brothers’ Almhouse and another large loft over the Old Kitchen Wing. She was keen to find out whether it would be possible to install internal nest boxes for swifts in these lofts. After careful examination, it was decided that as the first stage of this project, eight internal nest boxes would be installed in the loft over the Old Kitchen Wing. This loft had been recently converted so was fully floored which would make the installation much easier.

Gaps between the rafters
As the buildings at the Hospital are Grade I listed, it was essential to construct the boxes in such a way that they were not fastened to the ancient beams against which they would be resting. Tim Norriss and Roger Maynard visited again to make detailed measurements of each of the gaps between the beams and the eaves to ensure that the new boxes – designed specifically for swifts - would fit snugly and allow the birds to fly straight into the entrance of the box via gaps under the eaves.

Box in preparation
Over the summer, Roger Maynard constructed eight swift nest boxes, complete with a concave, and on the 20th September, he, Catharine and Tim returned to the Hospital to install them. The nest boxes fitted perfectly into the planned positions between the beams. Sheep’s wool was used to fill in any gap between the entrance to the box and the beams to make sure swifts could only access the nest box, not the loft itself. Some years ago, wire mesh had been fitted under some of the prevent jackdaws getting into the loft and in these places Roger carefully cut away the mesh so that swifts will be able to access the nest boxes easily and safely.

Swifts were seen prospecting for nest sites in the Old Kitchen Wing this summer precisely where the new boxes have now been fitted, so we are very hopeful that when the swifts return next May, some of them will take up residence in their newly created homes. Then, visitors to the Hospital (and their excellent Tea Room) will be able to sit at the tables outside and enjoy the wonderful spectacle of swifts zooming in and out of their nest sites.

Thanks are due to Catharine Gale for kindly supporting the costs of this project.

Installed next box

Tha Hanpshire Swifts Team!:
Tim Norriss, Catherine Gale and Roger Maynard

Monday 2 July 2018

A living wall for Swifts

This is an example of a simple, low cost way of providing nesting places for Swifts unobtrusively.

We previously described Swift boxes on a parapet here including examples in Tel Aviv, Israel. Here is another example in the Katzenelson Elementary School in Givatayim of incorporating nest boxes in a parapet wall. There must be many examples of parapet walls that could take a solution like this.

Parapets are usually high, well above any living space, no issues of cold spots or damp incursion in the building - indeed, an ideal location.

The only thing is to make sure the nest boxes are well defended from rain and sun.

There is a video showing how well it works, and the pictures below should explain everything.

Thank you to Amnonn Hahn for sending us these pictures.
Almost invisible entrances (click picture for a closer view)
Before attaching the boxes

Amnonn with the nest boxes

Easy access for inspection

A view of an entrance from inside

House Sparrows are nesting in number 25


Thursday 28 June 2018

The attitudes of housing occupants to integral bird and bat boxes

This post is about an important piece of research at the University of Gloucester, in partnership with the RSPB, by Sarah Roberts on people's attitudes to having cavities for birds and bats in their houses.

Starling leaving a Swift brick                         Photo Sarah Roberts

My summary of Sarah's summary (which you can read here) is:

This research aimed to investigate householder attitudes towards integral boxes for birds or bats in order to better inform housing developers and other interested stakeholders involved in establishing or promoting the inclusion of integral boxes into housing developments.

and, the bottom line is ......

Despite 3 out of 142 people having experienced problems, 2 didn't care and just 1 thought it was a bad idea. The other 141 either thought it a good idea (75%) or were neutral (24%).

Thus, should any architect or developer have fears that bird or bat boxes might have a negative effect on their ability to sell houses, they can relax. The evidence is that their houses become more attractive to the buyer.

There is a lot more detail in Sarah's summary

Monday 25 June 2018

Simple open eaves design

In 2012, I installed 6 under eaves boxes on the back of my son's house described here.
On the side of the house, I also boxed in the eaves in a very simple way. He has not lived there for 6 years, so I never visited, until recently, as he is moving back in.

by Dick

The reason for the visit was to rescue another Swift that had fallen into his drain. The cover that we fitted had seriously warped. The swift flew off OK, and at the same time there were about 20 swifts charging around his garden.

It seems that all 6 boxes on the back of the house are occupied and at least 1 of the 4 boxed in eaves boxes are occupied.

So I thought it worth documenting exactly how this was done. It should be self explanatory from the picture below.

It is constructed as a single sheet of plywood, spanning 3 joists forming 2 chambers with triangular entrances each end. A slot is cut in the middle to let the middle joist through and a wedge is screwed to the middle joist to separate the chambers. Battens each end close down the entrance size.

The home-made House Martih's nests have never been used, they are probably tucked up too far behind the fascia board.


Saturday 23 June 2018

West Cumbria Swift Group

In this story the actions of the councillor illustrate how making good the harm caused by unthinking development is almost only achieved through the actions of interested private persons. No legislation can do the job: only the endless vigilance of people who care for the environment in general and the conservation of swifts in particular.

bLesley Anne Archer-Shirley

Over the winter, with the Swifts away for nine months, a major project took place in Seascale. In the recent past, fascias had been put onto the Sports Hall blocking off several Swift nest sites. Only two remained. Ken Mawson, a local councillor, encouraged the Parish Council to back a project to put six Swift nest boxes on the Hall in the hope of getting more Swifts back into the building. A Parish Council grant paid for the boxes and Group members, along with a friend who had scaffolding, erected the boxes on May 3rd. just before the expected return of the Swifts. As it turned out we had longer to wait than expected!

The boxes chosen were ordered from John Stimpson via the website at a cost of £15 each [now £17.50].

They are made from exterior plywood with a plastic waterproof roof. Nest forms were also purchased and fixed in the corners furthest from the entry holes.

Right angle brackets were fixed to the back of the boxes after being bent to enable them to be hooked over a 2 cm thick plank. A further bracket was screwed to the underneath of the box. This would fix the box to the plank. This preparation meant that the work to be done on the scaffolding was made easier. Only two holes were drilled into the sandstone wall and plugged. The wooden plank was fixed leaving a gap sufficient to allow the boxes to be hooked over. Finally, a screw was put in place to fix the bottom bracket and keep the box in position.

Future removal of the boxes would be easier and only two holes were drilled into the wall. It proved to be a good method, if anyone reading this is contemplating a terrace of their own.

The ideal conclusion would be to attach a call system of Swifts on the nest but, as this was not possible here, we are hoping that the presence of the last two established nests further along the building will be sufficient encouragement.

West Cumbria Swift Group has been active this winter and further projects included:-
1. The erection of home -made nest boxes and call system in Low Seaton to replace nest sites lost when a property wall had to be re-built.
2. A ‘Filcris’ re-cycled plastic nest box and call system onto a house in Frizington where there is a large screaming party.
3. Nest boxes under the eaves of a house in Cleator Moor where neighbours did not want their Swifts and intended to put up fascias.
4. A barn/garage in Gosforth has been re-roofed over the winter with all the nest entrances left intact by an enthusiastic owner.
5. A terrace of 4 Swift nest boxes on a property in Gosforth with call system
6. Two home made Swift boxes with call system at Sleathwaite.

Last Year’s survey results (our first) have been submitted to the RSPB and Cumbria Biodiversity Data Centre in Carlisle and we are now attempting to re-survey the 54 nest sites we confirmed last season and monitor the activity at the new nest boxes.

For Swift Awareness Week we had an open evening on June 21st in Gosforth Methodist Church Hall. With slide show and several ‘stalls’ displaying nest boxes , call systems, nest box cameras, badges, booklets and leaflets. After refreshments, we watched the local screaming party perform over the hall.

We can be proud of what we have achieved in one year and hope that spreading the word about what can be done by a few enthusiastic individuals will encourage even more people to have a go to help these unique birds.

Saturday 26 May 2018

Swift boxes in an 18th century brick wall

Helen Copperthwaite of Millgate, Aylsham, Norfolk lives in an 18th century maltings, with walls 1.5 bricks thick. (~350mm). At least that's what we thought when we started. She was keen to have Swifts nesting in her gable - so being something new, we decided to have a go at it.

Helen kindly laid on a cherry picker, as it may not have been sensible to work all day on ladders at that height.

Our idea was to remove a header and stretcher from the outer wall, then drill out any brick remaining in the middle producing a cavity 350mm long and 85mm high leaving a half brick between the nesting place and the room inside.

We would then cut a 40mm wide piece off the outer stretcher, replace the header with a Cambridge System half brick entrance piece and we would end up with a very nice internal nest space 350mm x 185mm x 85mm.

Where the wall was 1.5 bricks thick this went very well according to plan:

Stretcher, header and bricks in centre of wall removed
Nest concave inserted - bedded down in mortar
Bill Murrells pointing up the inserted components
Sliced stretcher and entrance piece mortared in.
The mortar will dry to a good match with the old mortar
However, unknown to us, in some parts of the wall, the inner bricks had been removed and replaced by studs (timber) and insulation, so we had a wall  only 1-brick thick (~225mm). However, in the places that we broke through to the insulation there was always a stud against the wall. So we screwed a rectangular piece of plywood to the stud, completely blocking any access to the insulation, leaving a nest space 350mm x 175mm x 85mm, similar to the space above. We think this is a viable solution to any wall that is just 1 brick thick.

The final result was 5 new nest places:

5 new internal boxes embedded in the wall.
To demonstrate the principle of how we fitted boxes in the 1-brick thick parts of the wall, these illustrations might help.

Outside view
Inside view
[UPDATE June 2020 : 3 of the 5 nest chambers are occupied by breeding Swifts!]

Thursday 24 May 2018

Queen Anne Car Park Cambridge

We were asked by Guy Belcher of Cambridge City Council to dream up something for Queen Anne car park. It should be a good location, in central Cambridge, overlooking Parkers Piece. The location is high, but accessible from above The walls were not suitable for attaching anything directly to them.

So we came up with the idea of a 'Stretched Model 30' - 6 chambers in each of 2 long colony boxes. It was important that the boxes were beyond the reach of vandals with long arms, so to secure it, we designed 2 brackets to hang from the top of the wall.

The two boxes came from just 1 sheet of plywood 2440mm x 1220mm plus a bit more for the ends and internal partitions. The roof and ends are both covered in 9mm PVC fascia board, none of the plywood is exposed to sun or rain. The plywood back is well ventilated.

This installation took a lot less work than installing 12 single boxes.

Arrival at the top of the car park
Assembling the cabinets to the brackets
The boxes are positioned to avoid entrances vertically aligned. Photo Alan Clarke
Ready for installation
Final installation

Computer views inside and outside the wall
Using the same design, but different fixings Colin Wilson arranged for 2 Stretched Model 30's to be installed on Camberley Theatre in the borough of Surrey Heath. Two more are to be installed on a local shopping centre:

Photo Colin Wilson
Addendum 2:
[Update 2019 - one of the 6 chambers occupied in 2019] 
[UPdate 2021, 4 chambers are occupied by Swifts]
Another example in Cambridge, this time with a hinged roof

Hinged lid, with stop to prevent lid falling outwards
6 new boxes with an already occupied box, 1 of 3 occupied on this house
6 new boxes


Wednesday 23 May 2018

Swift boxes under very broad open eaves

Margaret & Ian Hobson of Beer in Devon asked us what would go best under broad open eaves, nearly 50cm wide, with about 33cm between the joists.

Beautiful view of the English Channel
Click to enlarge
The first idea was to have 2 boxes between each pair of joists with the entrances near the wall or near the outer edge. However, as we have no idea which the Swifts may prefer, we came up with a design for a double box between each pair of joists with one entrance near the wall and another near the outer edge.

We chose to give the entrance near the wall a landing platform, for no better reason than, in our experience, we have had more success with entrances near the wall with a landing platform than those without, but not enough evidence to be definitive. The landing platforms are grooved by making shallow horizontal cuts with a mitre saw.

The outer entrances face down at 45°. There are plenty of examples of success with sloping entrances e.g. the Zeist and Model 30 boxes.

As this was a new idea, we decided to have a go at it ourselves, and we then shipped the boxes flat-packed to their destination in Devon, where they were competently reassembled.

The boxes are installed by removing the bottom, screwing the sides to the joists, then replacing the bottom.

Preassembled box - landing platform on the right.
The bottom is configured so it is easily removed for installation.
It also provides a small step for the Swifts.

View prom above - 2 nice-sized chambers

Boxes reassembled, painted, concave glued down and feathered, ready for installation
4 double boxes installed