I have spent the last couple of days on a lime plastering course in Bedford. I am learning this skill so I can deliver more retrofit services to the customers of www.ecoalex.com. One of the key ways to improve the energy performance of older houses is to add internal insulation to walls. There are lots of people offering this service with celotex and other oil based insulation materials. These are very efficient and applicable in many more modern homes, however they do require careful installation of vapour barriers in the walls and have a risk of condensation. I want to be able to offer my customers something a little different, Natural Insulation. This will enable be breathable and allow moisture to pass through it naturally rather than gathering hidden inside the construction of the wall. After talking with a vegan customer I have been looking at wood fibre insulation in batts and boards. To get all this finished properly it needs plastering, modern plaster sets solid and isn’t breathable so I have been learning to work with lime.
There is a resurgence of interest in lime plaster at the moment, partly because of heritage projects like St Pancras station and partly because of a renewed interested in it’s flexibility and breath ability. This meant there was a choice of a few courses, however a lot of them were quite rural and a good distance from London so I chose DIY plastering in Bedford and I am very pleased I did. The course was one to one so I got plenty of help from Paul and could have it tailored to my requirements.
When I got there Paul had prepared two walls, one typical brick one and a second much flatter one to simulate the type of wall I am building using wood fibre insulation. After checking my fitness we agreed to try and plaster both walls so I could tackle any different lime issues. I started with the masonry wall applying two guides across the wall that would cover all the bumps and undulations and produce a flat surface. I then filled in with plaster and used a straight edge to get the plaster flat and even.
Then we left this to dry and I moved on to the flatter surface set up to simulate wood fibre board. Here I applied a much thinner coat of plaster, embedded some mesh in it and then a second thin coat. This was then flattened using the straight edge. Only 10-15mm of plaster are needed as the base wall is so much flatter than an older brick wall. Once these two walls had dried a little I went over them with a float, flattening the surface and adding some roughness for the skim coat. That was day one completed.
Day two was all about getting things smooth, very satisfying it was too. After drying overnight both walls had developed some cracks, especially the masonry one where we had a much thicker covering of plaster. Many of these could be sealed again with the floats but the larger ones needed a bit more compression from the trowel and some extra plaster adding. Next we added the top coat of plaster, this had more lime and less sand to make it smoother, but went on the same way using a trowel. Once the wall was covered with an even layer of topcoat we left it to dry. During this time Paul gave me a quick tutorial in filling holes in walls, very useful for my bathroom wall. Then I went over the wall with a float to even out the plaster further.
After this and some more drying I went over it with a trowel to get it even flatter and remove the air bubbles. It was all very pleasing to produce such a flat surface. At this point you can keep going making it flatter and smoother gradually using the trowel and the float. Looking forward to using the skills on an insulation project next month in Hertfordshire, get in touch if you would like me to help you with your house. I am based in Central London but can travel. There are lots more photos on my Google+ page.
I have joined the Flash programme funded by the Institute of Sustainability. It is supposed to help me take advantage of the low carbon economy http://www.instituteforsustainability.co.uk/flash.html I guess I will find out about that over time but the first workshop was useful. I went to a retrofit workshop at the Mayville Community Centre in Islington. This was still being built so the venue was interesting but it was a bit noisy inside. It does look good though:
After a general introduction we were put to work on some plans that we had brought in. This was particularly useful for me as a non-architect I got to learn a lot from their perspective, hopefully they learnt something from me as well. The first exercise involved us identifying thermal bridges from a plan and certainly got us thinking. In the second workshop I got to discuss one of my projects, a cold Victorian terrace and the input from the other delegates was invaluable I would especially like to thank Margaret Reynolds for her input.
Finally completed my CEEQUAL assessor course last week. This was something I signed up for when CIRIA made me redundant last year but with one thing and another I hadn’t managed to have free time to coincide with a course in London. Still the work I have been doing in the meantime meant that I was a bit more of an expert when it came to the ecology section.
I was pleased to discover that most of my civil engineering knowledge remained intact. In fact working on the M25 widening project meant I had much more experience of projects in action than previously.
They pushed us quite hard over the two days, not surprising really given the breadth of topics we had to cover. The section on energy seemed a bit vague at first but I suppose I had the advantage of doing a course on energy the week before (see last post). I think for a lot of companies it will be the first time they have thought about energy and carbon during construction and particularly in use.
The assessment divides into 12 categories starting with the project management which underpins it all and then looking at different areas of environmental performance in a civil engineering project. Ecology, for instance deals with all the improvements you can make and also avoiding any problems you can get like Japanese Knotweed and how they are dealt with. The methodology is a bit like the waste hierarchy, you score highest for not removing environmental features but you can make things back by introducing mitigation strategies and making improvements around the project.
Having learnt all this I am eager to get started on an assessment either for Ecology Consultancy or as a freelancer so let me know if you need one doing. I can also assess a project quite quickly and let you know how it might perform.
Completed the final free module of my course at the University of Westminster. They managed to persuade The Green Register to run a course for us. It was definitely the most rewarding course and it qualifies all the delegates to become members of their organisation.
We covered a wide range of topics from the basics of life cycle analysis to an in depth look at analysing the performance of different renewable energy technologies. It seems that Solar Thermal is about the most efficient way of generating energy at the moment, unless you happen to live on a hill and have a stream flowing past your house in which case a waterwheel is even better.
The course really covered a lot of useful stuff for sustainable construction and particularly helped me fill in some energy related knowledge gaps. There was also one module on the Code for sustainable homes which came over as quite a long way behind compared to the things we had learnt elsewhere on the course. Still at least it is encouraging people to improve their performance whether they want to or not.
Met up with some friends from previous courses too, I think we all liked this one best. A number of them are participating in projects as part of the course but I will only be able to go along to any fringe events now as I have used up my quota.