DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Concrete, Stone & Masonry (
-   -   Help with new block foundation (

stevekem 07-21-2013 10:28 PM

Help with new block foundation
Just had the block layed to replace an old foundation under a 14 x 7 addition on house.

1) On 1 side the old floor/sill plate is off level a good bit, about 1.5" over a 7' span. I had the block layed level and now on 1 end the block is against sill and other end of span there is about a 1.5" gap. I was going to fill in this gap with some cement/grout, but I am unsure as to what type to use. Any suggestions?

2) I was originally going to back fill with gravel against new block and put a footer drain in, but now after looking at grading there is no where to run it that will allow a downward slope for drainage. Should I still back fill with gravel if no footer drain is being used? Soil is hard clay with very poor drainage, so I am afraid if gravel is used, pools of water in gravel will sit against block and seep into walls. My thinking is if back filled with old soil/clay, it would prevent large pools of water from forming (that would be against walls) and be better than gravel in this case. Any thoughts on this?

3) I was going to waterproof exterior walls below grade and read a low cost method would be using a thick coat of tar with 6+ mill plastic over top and another layer of tar over plastic, would this be suitable?

Thanks in advance for any help!

stevekem 07-22-2013 08:06 PM

Anyone have any thoughts on this? Regarding question #1, should I use mortar, hydraulic cement or something else for this?

I am looking for the strongest material that won't break apart very easily when used to fill small gaps.

joed 07-23-2013 10:10 AM

1. nor sure I understand problem. Can you post pictures.
2.Is there a basement? Footer drain and gravel would be my choice. If it can't gravity drain then a sump pump is needed.
3. I would use a real waterproofing method. The plastic will eventually unbond from the tar.

stadry 07-23-2013 07:14 PM

meadows hydralastic 836 & drainage/waffle board ( miradrain ),,, ferguson carries drainage board as do many other const supply houses

ps - its not ' tar ' but a mixture of asphalt cement & water,,, in order to apply tar, you'd have to heat it to 200f & above

strategery 07-24-2013 09:34 AM

If there's no way to drain to daylight, is it possible to direct the water to a dry well or something?

stadry 07-26-2013 01:06 PM

the most important item is positive drainage ( AWAY from the wall ),,, backfilling w/heavy clay content material is sketchy at best due to the inability to properly compact the fill against a lo-lateral strength block wall as you're denied the use of mechanical plate compactors.

the ' something ' - we often bury a pvc sump ( proper depth ) & install a zoeller m-53 pump,,, we also use a pvc pipe riser to make pump replacement easy ( no digging up the sump )

All times are GMT -5. The time now is 12:10 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1