Raised observation deck and pier.

[Laurie61]

Hi all, this is a raised decking, built to make best use of a difficult corner plot in my garden. My problem was the ideal position in the garden already had a greenhouse in situ and I didn't want to move it, there was also a hedge forming a fence between myself and a farmer’s field. This could not be cut too low but there was a space between the two. Ideally, to be able to see over the obstacles, I needed a raised area and so looked at designing a platform high enough to give worthwhile views. Decking is usually raised just off the ground and my main worry was building a free standing platform sturdy enough for the job, the platform also needed to be big enough to be useful.

The design I eventually settled on was 1m high and 4m x 2.5m with an additional 1.5 x .5m section leading to steps and was situated in the south-east corner of the garden. Trees block my view to the north and northwest from this position, up to an elevation of 40/45dg, but I can see Polaris and do have good views in all other directions. The first job before starting on the decking was a pier base; there are various recommendations for telescope pier foundations which can go up to 1 ton per inch of aperture. At the time my main scope was 8.75in and I didn’t fancy putting nearly 9 tons of concrete in but wanted something solid without going to these extremes. I decided to make a box using engineering blocks, built off a concrete slab, which could then be filled with sand and capped. I would then be able to use a hydraulic ram; I had come by, as a pier for the eq mount. This took 4/5 days to do before starting on the deck. I had chosen 4m as the deck length as this was the pre cut length of the decking planks, which saved a bit of work, and the other dimension would also allow me to fit full width planks. I fabricated the box which would form the decking frame and put it on the ground where it would be built. I then used this to work out were the post holders would need to go and marked the floor. Post holders were knocked into the ground and some gravel put in the bottom of the boxes to try and preserve the post bottoms from rot. With these in, the posts could be fitted into the holders and the frame lifted to the desired height and fixed. I decided to slope the deck frame slightly to aid water run-off. I used allthread bar to bolt the frame to the posts, as well as screwing everything together, also using allthread to secure the all weather ply for extra security. I had chosen to use sheets of all weather ply to create a box structure and tie the posts together for extra strength. The timber had been pre painted before construction but everything was painted again and then the decking planks were layed. The deck was designed with a hole to allow the pier base to be accessible and the pier fitted, a gap was left around the base, in the deck, to isolate the base/pier from vibration. The last decking job was putting on the hand rail which is half round fencing rail. The hydraulic ram was then lifted onto the pier base and bolted down. This was 200lbs and together with the base weighed almost exactly 1 ton. I selected a hydraulic ram to use as a pier for two reasons, one is its incredibly solid but they also have a heavy rubber seal around the top of the unit which allows the internal bar to extend and retract. I thought this might be a good vibration damper and this has proved to be the case. I have permanently fitted a Fullerscopes MK3 EQ mount to this although I have tried a wedge and 12in lx200 just to see if it would cope and it was very solid.

A few photos of the build-

[Laurie61]

The mount and scope ready for action

[Tinker1947]

Nice solid pier, and stable decking, a job well done........

[laser_jock99]

Looks like a nice job you've done there.

[r3i]

Nice job - did you need planning permission to have the decking that high? See: http://www.planningni.gov.uk/index/advice/advice_apply/advice_apply_homes/advice_around_home/advice_home_fences.htm

[Laurie61]

Hi Mike, to be honest I had assumed it would be treated the same as a garden shed or outbuilding. So as long as the footprint was not excessive or built in front of the building line there would be no problems. Looking at your link does show that there are specific guidelines just for decking and so anybody wanting to do something similar might want to ask planning first. Thanks for the link.

[yesyes]

That link refers to Northern Ireland though, probably doesn't apply to Staffordshire... ;-)

[Gina]

Ahhh....

[r3i]

That link refers to Northern Ireland though, probably doesn't apply to Staffordshire... ;-)

Oops ..... Well spotted Chris, I should double check my Googling in future. I'll try again, is this link more appropriate: http://www.planningp...ojects/decking/ Same outcome I'm afraid, it still looks like decking must be lower than 30cm to avoid the need for planning permission.

[ollypenrice]

This is a very fine idea. Good thinking.

In the winter it will save you tramping mud around. If the planners get on your back just shovel some earth under it and raise the level of the ground.

Olly

[r3i]

If the planners get on your back just shovel some earth under it and raise the level of the ground.

Lateral thinking at its best

[Laurie61]

Good idea Olly. I think I'm safe anyway as its been up more than four years and planing can't make me move it now I think the rational behind the 30cm height rule is to stop you overlooking adjacent propertys?. This is built overlooking farm fields and wouldn't upset my neighbour's