I have two major problems I'm looking to solve. I have Radon gas infiltrating from my open crawlspace floor and into my house, and I have water penetrating through my crawlspace walls and/or floor from the yard. I have a natural spring that saturates the soil above (and north) of my house and flows toward my house in the Spring to mid Summer months, and in the Winter/Spring the snow pack/melt I think also saturates the soil around my crawlspace. It saturates about 20" of the soil and makes it too damp in the crawlspace for 4-5 months out of the year.
I'm trying to fix the drainage and the crawl space radon problem as passively as possible while also cleaning up the air quality in the crawl space, insulate it a bit, make it drier, and make some storage room for seasonal items. I've already plugged the 3 small vents and rebuilt the crawlspace door to make it pretty tight from the exterior openings.
I'm trying to solve the issues as passively as possible, without installing unnecessary materials and/or electrical devices (like sump pumps or radon fans).
As-is, on the wetter years like this past one I get about 1" of standing water on the part of the crawlspace clay floor that borders my west facing yard. it stays close to that westward wall, about 36" from it, and only about 3/4 to 1" deep at wettest time of the year, for about 2 - 3 months. I don't ever see water on the crawlspace walls, but I can see the salts leaching on them on the north and west sides, where the yard is really wet and higher in elevation.
I bought an electric radon meter. The radon reads between 15 and 30 in the crawlspace. Not super high but above the EPA's random 4 measurement.
I think I need at least a 20" deep PVC/gravel drain dug and installed in my yard, about 75 to 100' length, around the northwest corner of my house. It needs to divert water away from my crawl space walls/floor. This water comes from the natural hillside spring, as well as snow melt that comes from above the home's elevation. The drain can empty a few feet away from my home's southwest corner. I'll use it to water those small trees and such I have that can use the water. Maybe even fill a small 4' pond for the dogs.
After the drainage is fixed, I need my 36" to 40" tall crawlspace (that's floor to top of wall height), which is a 26' x 31' rectangle (or 806 SF) to be leveled enough to place 2 layers of 10 mil poly down and pour 3" of concrete throughout its floor. My crawl space floor is relatively clean and level at present but it will require some material to be moved around to pour the slab level, perhaps. I have saved some scrap plastics to put down below the new 10 mil plastic is laid to help protect it from punctures and provide extra insulation between the dirt floor and concrete.
So if the yard drain takes care of 90% of the yard water from reaching the crawlspace walls, but I still receive some slight water from underneath the crawl space floor, will the dual layers of plastic and 3" of poured concrete keep water from coming into the crawlspace from underneath? Or will drainage need to be installed on the inside of the crawlspace also, underneath the slab?
I want to avoid a sump pit and pump if possible. My crawlspace floor has a natural slope towards the south, so maybe a sump pump is not needed and the water can just be directed to drain through the CMU wall or under it, into the yard?
Suggestions on what is likely the best long term and most economical and simple fix for these issues? How's my plan sound? Thanks. Andy
I'm trying to fix the drainage and the crawl space radon problem as passively as possible while also cleaning up the air quality in the crawl space, insulate it a bit, make it drier, and make some storage room for seasonal items. I've already plugged the 3 small vents and rebuilt the crawlspace door to make it pretty tight from the exterior openings.
I'm trying to solve the issues as passively as possible, without installing unnecessary materials and/or electrical devices (like sump pumps or radon fans).
As-is, on the wetter years like this past one I get about 1" of standing water on the part of the crawlspace clay floor that borders my west facing yard. it stays close to that westward wall, about 36" from it, and only about 3/4 to 1" deep at wettest time of the year, for about 2 - 3 months. I don't ever see water on the crawlspace walls, but I can see the salts leaching on them on the north and west sides, where the yard is really wet and higher in elevation.
I bought an electric radon meter. The radon reads between 15 and 30 in the crawlspace. Not super high but above the EPA's random 4 measurement.
I think I need at least a 20" deep PVC/gravel drain dug and installed in my yard, about 75 to 100' length, around the northwest corner of my house. It needs to divert water away from my crawl space walls/floor. This water comes from the natural hillside spring, as well as snow melt that comes from above the home's elevation. The drain can empty a few feet away from my home's southwest corner. I'll use it to water those small trees and such I have that can use the water. Maybe even fill a small 4' pond for the dogs.
After the drainage is fixed, I need my 36" to 40" tall crawlspace (that's floor to top of wall height), which is a 26' x 31' rectangle (or 806 SF) to be leveled enough to place 2 layers of 10 mil poly down and pour 3" of concrete throughout its floor. My crawl space floor is relatively clean and level at present but it will require some material to be moved around to pour the slab level, perhaps. I have saved some scrap plastics to put down below the new 10 mil plastic is laid to help protect it from punctures and provide extra insulation between the dirt floor and concrete.
So if the yard drain takes care of 90% of the yard water from reaching the crawlspace walls, but I still receive some slight water from underneath the crawl space floor, will the dual layers of plastic and 3" of poured concrete keep water from coming into the crawlspace from underneath? Or will drainage need to be installed on the inside of the crawlspace also, underneath the slab?
I want to avoid a sump pit and pump if possible. My crawlspace floor has a natural slope towards the south, so maybe a sump pump is not needed and the water can just be directed to drain through the CMU wall or under it, into the yard?
Suggestions on what is likely the best long term and most economical and simple fix for these issues? How's my plan sound? Thanks. Andy