the yesyes observatory - the build

[yesyes]

OK, I'll remove the shuttering on the weekend. Though the suspense is killing me...

Doesn't look like hot-n-dry weather coming up any time soon again but I'll keep that in mind.

[yesyes]

Does anyone have any suggestions regarding that one foundation right next to the tree stump? Will that pose any problems?

[Gina]

Get the demolition men in and destroy that stump Seriously though, I don't know - a problem I agree All I can think of is an extra strong beam and no middle support.

[Bizibilder]

That stump will cause problems - it will start to slowly shrink as it dries and rots away. Eventually this may lead to the foundation moving - even for such a small building this would be a problem. You can usually find a local "stump grinder" who will remove it for you. They have a machine like a huge circular saw mounted on a trolley that turns the stump to sawdust quite quickly! They tend to go about 8"-10" deep so almost all the stump is gone. The hole would be a good place to put any old bricks or rubble.

[yesyes]

Hmmm, the problem is access to the garden. The tree surgeon who felled the tree said they would not be able to get their grinder machine back there.

[Bizibilder]

You can find grinders that will pass through a 24" gate - someone should have one, maybe the local hire shop as they deal with the DIY market?

[nightvision]

You could just straddle it by constructing a support to each side of it, that's if you have the space.

I have seen people drill them full of holes (helps provide oxygen) and burn them away using a small coal fire but it takes ages and the neighbours will probably get upset.

[yesyes]

You could just straddle it by constructing a support to each side of it, that's if you have the space.

I'm not quite sure I understand what you mean...

You mean to make the foundation around the stump in a U shape or similar? Or just make the foundation longer with the ends as far away form the stump as possible?

[nightvision]

I'm not quite sure I understand what you mean...

You mean to make the foundation around the stump in a U shape or similar? Or just make the foundation longer with the ends as far away form the stump as possible?

Maybe I didn't understand your approach correctly, I thought you were pouring corner blocks and then a block at half span (along the long sides) with the stump coinciding with the half span block. I was proposing you have a block each side of the stump roots. I need to go back and check your drawings and photos seems like I may have it all wrong, sorry for any confusion.

This is what I meant but maybe they would still be too close to the stump:

[Gina]

Yes, 4 supports along the length instead of 3. Sounds good

[yesyes]

I see...

The original idea was a T shaped footing as outlined in the attached image. Another T shaped footing will be on the opposite side. This is to support the middle joist on which the dividing wall will be built.

I could build them as you suggest but connect the 2 , then make the support for the middle joist rather short. I guess the trick is for the footing to not stand or lean on any wood / roots?

[yesyes]

This might explain the plan a little better.

red are the floor frame joists, either 4x4" or 4x6" (two 2x6" next to each other), haven't quite decided yet...

[nightvision]

I see, makes sense, I guess you could use 4 blocks across the back and just hang your dividing-wall joist off the rear beam using a standard hanger bracket. That way nothing is leaning on the stump.

[yesyes]

That might be a good idea. Thanks Tony.

[yesyes]

More progress today...

First I took the shuttering off the first 2 footings.

Then I made another 2 shutterings (is that the right word?) and filled one. That's the smallest one that is on top of the concrete slab. I'm out of ballast and need to order more before I can carry on with the remaining footings.

Pictures

1 - first footing

2 - and the 2nd one

3 - both together

4 - first new shuttering

5 - 2nd new shuttering with PVA at the bottom

6 - ... and filled with concrete

7 - both together

[Gina]

Massive foundations you have there Chris

[Astrokev]

More progress today...

First I took the shuttering off the first 2 footings.

Then I made another 2 shutterings (is that the right word?) and filled one. That's the smallest one that is on top of the concrete slab. I'm out of ballast and need to order more before I can carry on with the remaining footings.

Fantastic Chris! With foundations like that, your observatory is going nowhere!

[yesyes]

I shall hope so ..

They did turn out quite a lot bigger than I had pictured in my mind...

[yesyes]

Here is a picture of me mixing concrete :-)

[Gina]

Here is a picture of me mixing concrete :-)

Goodness me And I though it was hard work using an electric cement mixer Well, it was a whole day's hard work bucketing gravel, cement and water into the mixer and then turning it out into the hole and pipe to make the pier and foundation all in one go!!

[Astrokev]

Here is a picture of me mixing concrete :-)

Can't argue with that, although your calm unruffled expression makes me wonder if this is a posed set-up picture, with some lacky doing the hard graft just behind the camera! :wink:

[Bizibilder]

Power tools to mix concrete? Not for me!! :eek:

[yesyes]

Can't argue with that, although your calm unruffled expression makes me wonder if this is a posed set-up picture, with some lacky doing the hard graft just behind the camera! :wink:

No, this is not a set-up, only me looking at the camera is. You'll see when someone takes a picture of you working on your own obsy. You'll have the same smile.. ;-)

Though I have to admit yesterday I only mixed 2.5 bags for that one footing and the photo is showing me getting started on the first bag. The other 2 footings were much more exhausting.. ;-)

[yesyes]

Goodness me And I though it was hard work using an electric cement mixer Well, it was a whole day's hard work bucketing gravel, cement and water into the mixer and then turning it out into the hole and pipe to make the pier and foundation all in one go!!

Actually, the power drill method works a lot better than I had expected.It took me only 2.5 hours to mix and pour these 2 big footings.

I'm still considering renting a mixer for the pier base though. That's probably going to be more concrete than all the footings together.

[r3i]

I used a sheet of DPC which was about 4ft square laid on the lawn - I put the cement and ballast onto it then rolled the edges from side to side to mix it with water added a bit at a time. As long as I was careful not to spill it over the edge I could mix a decent quantity of concrete quite quickly then lift the sheet by the 4 corners and pour it where it needs to go.