Do i need to put in a sub-base? - Do i need to put in a sub-base?

[DNgroundworks]

why does it make a difference Tony? I have only ever used terram

[syec]

Do i need to worry about drainage? I was think of having a limestone chippings border between the end of the patio and the sleeper retaining walls, and sleeper steps, so at the bottom of the fall, about 75mm deep, on top of compacted type 1, will that be enough?

[lutonlagerlout]

why does it make a difference Tony? I have only ever used terram

weeds can get through woven fabric,with non woven they cant get through ,but the water can the other way
never seen terram down south only wrekin multitrack
LLL

[syec]

I found terram groundsure 900 2.5m by 25m for 40 quid, inc delivery on a site called flexiblelinings they had big packs too, or you can buy it from the terram site direct but it was a bit more expensive

[syec]

Hi All,

Still digging, a bit worried I have gone through too many of the fibrous roots of the oak tree in my garden, haven't hit any big ones but am now scared its going to fall over!!! Anyone any ideas?
Also, I have seen SBR mentioned a few times when mixng the bedding layer, what is that? Is it plasticiser?

Thanks

[GB_Groundworks]

You are joking about the oak tree right?

I've seen the aftermath of 20ton truck smashing into a mature oaks at 30 odd mies an hour and it had only scratch the bark, even a little tree 10cm girth takes a massive force to pull it out.

The fiberous roots are for food and water the tap roots anchor them, don't worry it'll be fine.

[syec]

Well half joking, i am worried, but as you say i had read they are only for food and water, so i am sure it will be fine, well i hope it will. I had my only full day diging on saturday, head down stuck into it then at the end of the day i looked up and thought, hmm i am a bit close to the tree now, the closet point is about 2.5 m away about where i am about 0.5m deep, the tree is infront of the right edge of the hole in the photo.
But I have not gone through any root thicker than about 3 or 4 cm, most of them around 1 to 2 cm they are pretty flexible and i just go through them with the spade.

What do you think?

[GB_Groundworks]

I've spent days in 16 ton diggers trying to pull out oak stumps there very well anchored

[syec]

Thanks Giles, put my mind at rest, been waiting for the wife to ring me at work all week telling me the house is now a bungalow!

Now back to the job, what is SBR and do I need to add it to the bedding mix?

[syec]

Its coming along, did the sleeper steps and edges this weekend, type 1 will be next weekend, then lay the slabs the weekend after. The finished height should just be above the bottom of the bottom step.

I found this, Everbuild SBR5L S.B.R bond 503 5L, before I order it, is this the right, stuff? how much should I put in each mix? if thats not a stupid question.
Thanks

[Thehandmadegarden]

No need for SBR in bedding mix. SBR can be used if there is a risk of the paving being stolen Before you lay the type 1 you need to fill those voids under the sleepers with a dry mix concrete packed in with a sledge hammer or stout timber. Have you remembered to treat the cut ends of the sleepers with Ensele? if you don't you don't have tanalised timber!

Clive

[syec]

Thanks Clive, i was planning to pack the voids with type 1 and no I didnt treat cuts! I will treat the one I can get to

[lutonlagerlout]

No need for SBR in bedding mix. SBR can be used if there is a risk of the paving being stolen Before you lay the type 1 you need to fill those voids under the sleepers with a dry mix concrete packed in with a sledge hammer or stout timber. Have you remembered to treat the cut ends of the sleepers with Ensele? if you don't you don't have tanalised timber!

Clive

i always use SBR in bedding mix clive
makes it a better mix and sticks like s*&t to a blanket
at roughly £30 cost on an average patio i ts a no brainer for me

also i thought "tanalised" meant pressure treated,as in the whole of the timber?

ps not really happy about the voids at all,would have been better to lay the timbers on 150mm of leanmix fully supported,but ramming it in is better than nothing
LLL

[syec]

I put a bag and a half of concrete under each end of each sleeper, thats 75kgs per sleeper, will that not be enough?, it looks a bit weedy in the photo but it seems pretty solid, and the whole thing is fixed together with 200mm timberlok screws, well its too late now i suppose! Will pack some thing in there then

[local patios and driveway]

Use sbr. It will help the bond, its not there to stop someone stealing your slabs.... :rock: