The Big Pond Project - Part 3

Its been a while since I last collated where we are up to with our Koi Pond Project and quite a lot has happened. So I thought it was about time for another update (see here and here for the earlier updates). 

The blockwork for the pond has now been fully completed, we were pretty much done at the last major update but have finished off the last few blocks. This was tricky due to the weight of the blocks and needing to lift them up the ladder onto the final position. The walls of the pond have ended up over 6 feet tall. 


With the blockwork finished we were then able to turn our attention to the filter house and fit the remaining ship lap cladding to the pond side, as well as make doors to finally close off the front of the building. We opted for double doors to make it easier to get large filters into the filter house. Once the wood work was all done Mark got stuck into the painting and its now all primed and painted in pure brilliant white paint. 

The most dramatic change has been the construction of the pergola over the top of the pond. This has several purposes, making the area more private as this part of the garden is quite overlooked, as well as providing shade to the pond which will help reduce algae and green water. We also like it for its aesthetics as well. In addition there are several herons that live nearby and shielding the pond from them should reduce the risk of problems. 

We used chunky wooden uprights (6"x6") which were fixed in position using metal rods and for extra strength brackets were also fitted. The brackets will be hidden by a wooden cladding round the base of each post. At the top of the posts we notched out a section of the wood to allow the main supporting beam to fit flush to the posts, this sounds easy but cutting out a neat square of wood from a large wooden post took quite a bit of time, and several adjustments to get it just so. The main frame of the pergola was built from 4"x2" timber, supported in place by joist hangers. We found quite a good rhythm by the end and was getting them up fairly quickly. Noggins were added between the joists in a brick-bond pattern to give extra strength and prevent the wood from bending. It was amazing just how much extra strength these seemed to give and the whole structure was much more rigid as a result. 

My Dad lending a helping hand

Mark took on the rather unenviable task of painting everything, whilst we had completed the primer coat of paint before assembly the final two coats of paint went on after construction. In an ideal world it would be better to have got at least another coat of paint on before construction, but this was where the weather didn't help. The rainy June and early July made it difficult to paint, so we got stuck into building. Once the weather improved the top coats went on. 

The pergola turned out to be slightly trickier to build than anticipated, partly due to the shape of the pond - the depth meant we needed to use ladders for pretty much everything we did, and also its not a perfect rectangle, the first corner of the pond has a triangle shape missing to enable the pond to blend in to the neighbouring planting area and allow a sweeping curved path to enter the seating area. We could have made life easier by making the planting area fit to the pond, but I was keen to make the pond follow the curved path rather than the other way round.

Twinkles doing her best tiger impression.

Painted with just primer, prior to two final coats of paint

As I mentioned earlier one of the jobs of the pergola is to provide shade to the fish and privacy to us. So with that in mind we had selected a semi opaque polycarbonate covering for the roof. The sheets were 4m long and 92cm wide, big sheets and although lightweight are cumbersome to move about. We placed each one on the roof, marked it, brought it back down to a makeshift working area in the pond and then cut each one to fit. We had carefully assembled the pergola to fit the polycarbonate sheets, although it turned out a couple had been supplied that were slightly wider than they should have been, so we had to make minor adjustments to make them fit. 

Completed polycarbonate roof

Now that they are all up and in place the final result looks good, so although they were fiddly to do I'm really pleased with the way they look. The roof slopes to the back of the pond (at a 1:20 slope), as we didnt want the rain water to splash off and over the neighbours fence the final touch was adding guttering (white of course!) to take the rain water to a soak away. 

Now the major work is finished we have started adding large sheets of foam-board insulation to the walls of the pond. This has two functions, to insulate and help maintain water temperatures in the winter, and also to give a smoother finish than the blockwork walls when the pond is fibre glassed. 

Hopefully fitting the foam board will be finished this week as well as fitting the window frame which will finally have us ready for fibre-glassing! Stay tuned for the next installment! 

 Gaz :)

Posted in: exotic garden , Koi , Pond build , Tropical Garden