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rscho January 1st 06 01:30 PM

subfloor crawl space
 
I've had to remove a few T&G floorboards near some walls to replace
rotten joists in a cavity brick house. In order to get underneath the
boards I had to dig out about 6-8 inches of rubble (bricks, mortar and
clay soil) making a space of about 1'4" so I could crawl around. Having
replaced the rotten joists (and fixed the drainage problems that caused
them) I don't know whether to return the rubble, replace with a cleaner
& easier draining (and less smelly!) fill like crushed rock or leave it
cleared. The ground level underneath the house is now about 5" lower
than that outside the house.

Any suggestions would be appreciated.

Rick January 2nd 06 12:52 PM

subfloor crawl space
 
On Mon, 02 Jan 2006 00:30:08 +1100, rscho wrote:

I've had to remove a few T&G floorboards near some walls to replace
rotten joists in a cavity brick house. In order to get underneath the
boards I had to dig out about 6-8 inches of rubble (bricks, mortar and
clay soil) making a space of about 1'4" so I could crawl around. Having
replaced the rotten joists (and fixed the drainage problems that caused
them) I don't know whether to return the rubble, replace with a cleaner
& easier draining (and less smelly!) fill like crushed rock or leave it
cleared. The ground level underneath the house is now about 5" lower
than that outside the house.

Any suggestions would be appreciated.


I have always left mine clean and empty when I have cleaned them out
so I can gain access.

If nothing else, it saves cleaning it all out again next time.

Rick


Bob January 2nd 06 01:09 PM

subfloor crawl space
 
Because the ground around the home is higher, the ideal thing to do is to
provide good water run off. Do not back fill under the home at all, because
the more air circulation, the better it will be. If water gets down there,
it will not only rot the wood, but can cause mold. Install a submersible
sump pump in the lowest spot, with some kind of access door for maintenance.
If you back fill, and the dirt gets wet, it's much harder to dry it out.

"rscho" wrote in message
. ..
I've had to remove a few T&G floorboards near some walls to replace
rotten joists in a cavity brick house. In order to get underneath the
boards I had to dig out about 6-8 inches of rubble (bricks, mortar and
clay soil) making a space of about 1'4" so I could crawl around. Having
replaced the rotten joists (and fixed the drainage problems that caused
them) I don't know whether to return the rubble, replace with a cleaner
& easier draining (and less smelly!) fill like crushed rock or leave it
cleared. The ground level underneath the house is now about 5" lower
than that outside the house.

Any suggestions would be appreciated.




calhoun January 2nd 06 01:26 PM

subfloor crawl space
 

"rscho" wrote in message
. ..
I've had to remove a few T&G floorboards near some walls to replace rotten
joists in a cavity brick house. In order to get underneath the boards I
had to dig out about 6-8 inches of rubble (bricks, mortar and clay soil)
making a space of about 1'4" so I could crawl around. Having replaced the
rotten joists (and fixed the drainage problems that caused them) I don't
know whether to return the rubble, replace with a cleaner & easier
draining (and less smelly!) fill like crushed rock or leave it cleared.
The ground level underneath the house is now about 5" lower than that
outside the house.

Any suggestions would be appreciated.


Spread it out and cover the entire ground area with a sheet of 6mil poly
before you close it back up.



Stretch January 2nd 06 01:27 PM

subfloor crawl space
 
Where you are located has a bearing on the answer. Here is a link to
an article on drying out crawlspaces:

Crawlspace problems:

http://www.contractingbusiness.com/C...S=&NI L=false

Stretch


[email protected] January 2nd 06 01:29 PM

subfloor crawl space
 
You're correct to be concerned about the difference in level between
inside and outside.
You don't say what "the drainage problem" was.
Certainly, as Rick says, it's a good idea to leave the working space
below the floor.
As Bob notes, the problem is to keep water out of the space.
As long as you think you can keep the crawl space dry, you are o.k.
In addition to directing roof run off well away from the house, sloping
the yard surface away from the house, sodding for improved run off, and
making sure of the water table height, you might consider directing
some conditioned air into the crawl space. This can be done with
passive registers or a fan.
In the South East, outside air is often too humid to be useful in
lowering the relative humidity in crawl spaces.
TB


raden January 2nd 06 01:33 PM

subfloor crawl space
 
In message , Rick
writes
On Mon, 02 Jan 2006 00:30:08 +1100, rscho wrote:

I've had to remove a few T&G floorboards near some walls to replace
rotten joists in a cavity brick house. In order to get underneath the
boards I had to dig out about 6-8 inches of rubble (bricks, mortar and
clay soil) making a space of about 1'4" so I could crawl around. Having
replaced the rotten joists (and fixed the drainage problems that caused
them) I don't know whether to return the rubble, replace with a cleaner
& easier draining (and less smelly!) fill like crushed rock or leave it
cleared. The ground level underneath the house is now about 5" lower
than that outside the house.

Any suggestions would be appreciated.


I have always left mine clean and empty when I have cleaned them out
so I can gain access.


It also allows better airflow

I ended up with some rot after the previous owners of my house made a
though lounge and left the wall under the floorboards



If nothing else, it saves cleaning it all out again next time.

Rick


--
geoff

Bill Gill January 2nd 06 02:08 PM

subfloor crawl space
 
rscho wrote:
I've had to remove a few T&G floorboards near some walls to replace
rotten joists in a cavity brick house. In order to get underneath the
boards I had to dig out about 6-8 inches of rubble (bricks, mortar and
clay soil) making a space of about 1'4" so I could crawl around. Having
replaced the rotten joists (and fixed the drainage problems that caused
them) I don't know whether to return the rubble, replace with a cleaner
& easier draining (and less smelly!) fill like crushed rock or leave it
cleared. The ground level underneath the house is now about 5" lower
than that outside the house.

Any suggestions would be appreciated.


The crawlspace under my house has always been lower than
the outside yard. When I first moved in I had a
moisture problem, but I figured out where it was coming
from and corrected it and now have a dry crawlspace.
The main thing is to make sure where any moisture is
coming from and try to keep it out. Sometimes this is
easy, mine was, and sometimes it isn't. It can involve
extensive sculpting of your yard to redirect rain flow,
or french drains, or something of the sort.

The main thing I am saying is that having the crawlspace
lower than the outside is not necessarily a bad thing.

Bill Gill

Jay Stootzmann January 2nd 06 04:43 PM

subfloor crawl space
 
Check out
http://www.advancedenergy.org/buildi.../crawl_spaces/

for more info on crawl spaces

wrote in message
oups.com...
You're correct to be concerned about the difference in level between
inside and outside.
You don't say what "the drainage problem" was.
Certainly, as Rick says, it's a good idea to leave the working space
below the floor.
As Bob notes, the problem is to keep water out of the space.
As long as you think you can keep the crawl space dry, you are o.k.
In addition to directing roof run off well away from the house, sloping
the yard surface away from the house, sodding for improved run off, and
making sure of the water table height, you might consider directing
some conditioned air into the crawl space. This can be done with
passive registers or a fan.
In the South East, outside air is often too humid to be useful in
lowering the relative humidity in crawl spaces.
TB




Stretch January 3rd 06 12:21 PM

subfloor crawl space
 
Don't run AC into the crawlspace. It will pull the main house into a
negative pressure which will suck crawlspace or outside air into the
house. This will reduce performance of the ac and heat serving the
house. It can also backdraht a flue and kill you. Far better to put a
dedicated DEhumidifier in the crawlspace and close the vents after you
put plastic on the ground. To try to condition the crawlspace with the
vents open is like running the ac in your house with the wimdows open.

Stretch


rscho January 3rd 06 02:34 PM

subfloor crawl space
 
Thanks for all the info,

The drainage problem was a blocked storm water drain caused when whoever
put up the fence drove a post through it and then set it with concrete.
This allowed the roof run-off to overflow and enter the crawl space.
Judging by the age of the fence it must have been at least 20 years ago.
The previous owners seemed to go to considerable lengths to control the
resulting rising damp (its an old house with inadequate or no damp
course) but never seemed to attend to the drainage problem.

The average afternoon relative humidity here is about 55% (SE
Australia). Closing the crawl space really goes against the grain as
everything I've come across regarding rising damp or rot suggests
increasing ventilation but I guess if the outside air is carrying more
moisture than the crawl space air it makes sense! In any case I will
never be able to get access to all of the crawl space (without ripping
up all the floors) to lay poly effectively so I'm thinking of relying on
low voltage sub-floor ventilation fans that turn on and off depending on
the atmospheric conditions eg. turn on if outside air is drier than the
crawl space air.... or perhaps let natural ventilation take it course
and move on to the next project..

thanks again everyone!



Jay Stootzmann wrote:
Check out
http://www.advancedenergy.org/buildi.../crawl_spaces/

for more info on crawl spaces

wrote in message
oups.com...

You're correct to be concerned about the difference in level between
inside and outside.
You don't say what "the drainage problem" was.
Certainly, as Rick says, it's a good idea to leave the working space
below the floor.
As Bob notes, the problem is to keep water out of the space.
As long as you think you can keep the crawl space dry, you are o.k.
In addition to directing roof run off well away from the house, sloping
the yard surface away from the house, sodding for improved run off, and
making sure of the water table height, you might consider directing
some conditioned air into the crawl space. This can be done with
passive registers or a fan.
In the South East, outside air is often too humid to be useful in
lowering the relative humidity in crawl spaces.
TB





Dave Fawthrop January 3rd 06 02:35 PM

subfloor crawl space
 
On 3 Jan 2006 04:21:02 -0800, "Stretch" wrote:

| Don't run AC into the crawlspace. It will pull the main house into a
| negative pressure which will suck crawlspace or outside air into the
| house. This will reduce performance of the ac and heat serving the
| house. It can also backdraht a flue and kill you. Far better to put a
| dedicated DEhumidifier in the crawlspace and close the vents after you
| put plastic on the ground. To try to condition the crawlspace with the
| vents open is like running the ac in your house with the wimdows open.

Utter and complete Rubbish.
--
Dave Fawthrop dave hyphenologist co uk
17,000 free e-books at Project Gutenberg! http://www.gutenberg.net
For Yorkshire Dialect go to www.hyphenologist.co.uk/songs/


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