The workshop began with a mock up tests of little elements – wall, roof and brick. This was an exercise to get familiar with the local materials, crafts and masons. It then moved on to combination of the different designs into a single pavilion, with input from Gao. When design was confirmed, the construction began with the collection of materials and then the actual building of the structure.
Design was not so important in this workshop, especially when there was not a function allocated to the pavilion, other than to look onto the Guest House. It was meant as a temporary structure, for two years and will be demolished when the community centre is built on the same location. I learnt more about the design of joints and elements than the design of the whole structure. However, it was interesting that the aim of the pavilion was to be a catalogue of different material connections and possibilities in the village. If the design actually was that, it would have been very interesting.
People’s opinions about materials – mud bricks and not able to reuse it; grey bricks and its beauty; mortise and tenon and needless to use nails; social stigma
Chinese architecture is inward-looking. There are joints that you don’t see and the magic happens on the inside.
Bricks are divided into several types in this village.
- Grey bricks (Qing Zhuan) are traditional materials used in the Guest House. They are soft bricks, fired slowly with charcoal in special urns, over water. After they are fired, they are then clamped and sanded against each other to create a smooth surface on the facing side. This process takes a long time. The masons are very proud of the historical technique and the beauty that it creates. However, they no longer do it because of the complexity and effort. The mortar used for this is then usually gypsum mixed with organic glues found in crops.
- Red bricks (Hong Zhuan) are common materials found now in the village and area. They used to be made in the village by the villagers but now can be bought simply on the market. They are fired in urns quickly and so they are harder and cannot be sanded. The result is a rough finish. This kind of bricks come in two sizes, 10, 20, 30 and a smaller size. The mortar used is normally gypsum or cement with gypsum for decorative lining.
- Mud bricks (Tu Zhuan) are traditional materials used in common houses in the village and area. They are made with sand and water and air dried. If left out to dry in the sun, the surface might dry too quickly and crack. The way to test the mud bricks is to drop it on the ground from head height and see if it withstands the impact. There is also mud mortar made from the same material and could be used as temporary or permanent joints. Mud bricks cannot be reused.
Brick construction techniques
We wanted to test the wall and the points of insertion for timber – a typical condition found in the timber-brick buildings. Together with the mason, we first laid out the typical wall types used in construction in the village (Appendix a) and then tried one typical way of inserting a timber beam into the brick wall (Appendix b). The current way of insertion either leaves a hole in the wall while constructing it, and hence disrupts the pattern, or knock out a hole in the wall post-construction which damages the structural stability of the wall. We wanted to test if there is a way to allow for flexibility and stability at the same time. The different ways of new walls were made to create holes at regular intervals along the length of the wall. Timber elements such as beams, purlins, staircases or even furniture can then be inserted into the wall. This idea of flexibility also comes from the buildings in the village which are constructed at different times for different purposes. Flexibility allows for practical expansion of the buildings. The title of the mock up was engineered holes.
However, during the testing of these mock ups, there needed to have a tie-brick in between the two walls to ensure structural stability. Working the tie brick into the patterns then became a challenge and in the end we resorted to overlaying the layers of bricks in cantilevers to eliminate the need for tie bricks (Appendix c). Another important point to consider is the position of the beams. The location of holes in the wall has been arbitrary but the angle of the roof is standardised to be 1 in 2 (40cm length, 20cm height) in order to make sure that the roof tiles can sit properly and angle is sufficient for water drainage, but also because of the use of bricks and half bricks. Therefore, adjustments also needed to be considered to the wall to allow for the beam position.
There are also holes made in the upper parts of the walls of typical brick building so as to insert beams into it to build the second storey. The holes are then later filled with mortar or half bricks. In the construction of a typical brick room, bricklaying begins from the corners and moves inward. The bricks in the middles could be half-bricks.
Mortar placement was an interesting exercise. The typical way of placing it was to scrape on the sides and none in the middle or the side of the bricks. During actual construction, this was deemed to be unsafe as there is insufficient amount of cement/mortar between the bricks. Also, the masons use mortar to level the bricks because of the uneven sizes of the recycled bricks. This was also deemed to be structurally unsound.
In terms of foundation, the retaining walls and the columns should be tied in together to withstand horizontal forces. However, during the construction of the pavilion, some areas were not tied in together and the columns have to be rebuilt.
During construction of the pavilion, we wanted to test this technique and insert a staircase into the wall. However, one of the major problems with this is that the wall must be tall enough and have a sufficient amount of mass above the staircase in order to hold the timber elements down. Having a half wall does not allow for such a technique and this brick wall became more decorative than functional.
Material and gathering
Typical timber in the area is Chinese fir, Kampur and pine. Kampur is the cheapest and most common one. There are some historic forests in the area but to fall trees in there would need the trees to have died first. In India apparently they nail steel bars in a circle around the tree trunk and the tree will die. Kampur and fir are planted and felled with permit. The best kind of timber is regrown timber (chopped once and regrown from the same stump) and they are not easy to be corrupted. Typical ways to waterproof the trees is to apply layers of Tong Oil, which prevents it from termites and also rain. It is also advisable to lift the timber 20cm away from the ground to prevent water from entering into it.
On the hills behind the Big House Group of Fairy Water Village, there is a forest of Eucalypts which is forested to make paper. It is grown by the government as it grows very rapidly. However, because of the its need for a massive amount of water, it damages the soil.
Historic trees could also apply for licensing and protection. Once the tree is licensed, anyone trying to harm it is punishable by law.
Termites were present on site and a termite expert was invited to examine the site and the Guest House. Termites are scared of sunlight and dig tunnels to protect themselves from the sun. They leave traces which are visible as elevated tunnels of soil. Once disturbed, they escape and are difficult to find again. The best way to deal with termites is to first leave it and then leave possibilities to trace it. To get rid of termites, either find the queen termite, extinguish her and then the colony will die, or poison the termite/soil. The second way is the most typical but is harmful for health. When there are young children, it is advisable to leave the building for a week before opening it to this particularly vulnerable group. There might also be a type of poison that affects the termites as they communicate with each other.
Recycled timber is available cheaply around the village and there are houses with new, unused timber or old timber from demolished houses. When MM brought us around the place, it was interesting that she would point out the old buildings and how we can demolish it to get this piece of timber or that wall of bricks. Obviously these buildings do not matter in her eyes or even the villagers’ eyes. The contrast between the attitude towards this building and towards the Guest House is quite different. The quality of recycled timber is not very clear. It was not a good idea to do material viewing at night. We could have insisted more on buying new timber because that would have saved us time and labour costs in processing the old timber pieces.
Using recycled timber was difficult in terms of communication with the carpenter. However, I do feel that this carpenter is a special case. The rest of the people were much easier to communicate with. We (me and Jeff) began with showing him the 3D Rhino model of the design. It is understandable that this is not very clear. We then moved on to giving him plans and sections of the structure. However, spending the first two days doing mock ups we realised that the plans and sections do not communicate our ideas to him and he is building things that are not out intentions. Following that we decided that the easiest way is to make a physical model so that he could see the structure – also very importantly the different levels of the ground. The model was made of chopsticks and scrap wood pieces and was labelled heavily to simplify the process for the carpenter. This was successful as the discussions were able to focus on the model and we could pin-point which joint and beam we are discussing etc. The carpenter also referred to the model often when he is working to ensure that he is making the joints right.
The model also served very interestingly as a conversation piece between us and the villagers/curious onlookers. I had placed a pile of paper near the model to invite people to write their comments, although this was not very successful. However, having that physical and visual representation of what we are trying to build is an important communication tool to reach the villagers. It might also be that any structure that we build in the future, there is a communication through physical models. Maybe the design involvement and workshop could use models instead of drawings.
Timber is fixed onto each other with mortise and tenon joints (Appendix e). We observed the carpenters making these joints and recorded the process. When a new set of equipment arrived we sanded the chisels and axe and participated in the making process, starting with making a work bench (Appendix f). Beams and columns are locked into each other with mortise and tenon joints and end pegs. The beams could be stacked on top of each other and connected together with pegs to make thicker beams. The beams have to be vertically staggered to minimise compromise to the timber and not creating a four-way hole at any one point of the timber. The direction of the beams (vertically or horizontally) is controlled not by the position of the mortise but by the shape of the tenon (angled or straight). The pieces are made off-site and then transported on-site for assembly.
Connection between timber and brick became problematic. This is because the brick columns were standing alone and unstable when finished and there is a need to lock in the bricks column with the timber column. THe more continuously connected the structure is the more stable it is. The current practice is to place the timber on top of the brick. The team was unsure that this is sufficient joining between the two different materials. There were two proposed solutions, one to add a metal plate on the bottom of the brick, subject to the availability of steel plates. The other is to make timber parts on all columns which then act as clamps to prevent the timber from sliding off (Appendix d).
The other issues on structural stability included the viability of timber columns that have cracks in them. There were doubts whether the cracking is a cause for concern. The carpenter was not worried as apparently only cracked wood is able to dry properly. However, some of the timber has huge cracks across the length of the wood and we ultimately decided to use a thicker piece of timber to replace these cracked ones. The other option is to use steel ties to tie around the timber, however, these were not readily available (Appendix d).
The structural stability of the two standing columns were an issue. The proposed solutions included knocking them down and making a new wall tied into the columns so that the columns could at least withstand one direction of the horizontal forces. Negotiations with the workers resulted in a compromise using a different solution as they have already rebuilt columns twice and are very happy about redoing work again. This solution is to make a timber clamp in between the two columns and hold them together. This could also be applied to the other side and thus unsure that on both directions there is resistance (Appendix d).
Construction on Site/Brickwork
Clearing the site – work on site started with clearing the vegetation and grass. This included burning the site. However, this could only be done when the vegetation has been cut and left out to dry for at least a night. This way we can ensure that it will actually burn.
Fengshui – there is not much belief in Fengshui in the area. MM and Gao seem to have more respect for the Fengshui than the actual villagers do. This is something interesting – Fengshui is now viewed as a part of the culture of Chinese architecture and something to be respected and imposed from the outsider, as a method to reconnect to the past almost.