I own a post and beam home built in 1955 with a foundation issue which is causing a ½ sag on the floor as read by a level and tape measure within 3 feet of the foundation and outside wall. This is causing the prefinished wood floors all over the house but most particularly near the problem to move apart. The roof is new and there are no issues as of yesterday.
Poured concrete wall (footer between two inches and six inches under ground level and about 8” tall and 10” thick) with two rows of concrete block stacked on top, a wood sill plate (2”x6” or 2”x8”), then the T&G subfloor (2 ¼” thick) and finally prefinished ¾ kempas hardwood inside the home.
There is no concrete floor – it’s a dirt crawlspace. There are no cracks all the way thru on the poured concrete footer (south bedroom) which spans 20’ (8” tall x 10” thick) or in any of the blocks. However there are two minor (not extending thru the wall and very thin (1/16”) cracks on the exterior of the concrete footer in the middle of it two feet apart from each other. There are no cracks on the concrete footer inside the crawlspace. Also, no other footer walls have any issues. But, 30’ away in the center of the long east footer three rows of concrete blocks form an exit box out of the crawlspace and there a complete fracture up through all three rows of block appears. But they are not inline on the east footer, they are part of a boxed out exit area only. Yet, the foundation is formed around them underneath them.
Layout of the Home and Problem:
The problem foundation wall is on the south east of the home and juts 8’ out, from the center support of the home – the fireplace in the living room, to hold up the most southern bedroom on the south east of the building. When we bought the home three years ago evidence that this area from the last crawlspace southern beam which is stable all the way across the bedroom; from it three feet to the foundation wall was sagging. We did nothing and had only minor movement problems until two weeks ago.
Water Intrusion: Until 6 months ago water was getting into the crawlspace. It has been dry since that time. We added a gutter to the south side of the house replacing the scuppers that could not handle the rain or would clog from pine needle drop that always occurs. The area around the south bedroom footer has been dry ever since. Yesterday, we dug three feet under the southern foundation wall at the two corners and the middle to check for water and found it dry.
An Unusual Winter
We have had an unseasonably warm winter this year in Denver. Long stretches of 50 and 60 degree days (with 30 degree nights) and short spells of very cold days, some even below zero, have produced crocus and buds on some trees at least a month early.
Strange Happenings for the Last Two Weeks
The three year old kempas wood floor (the entire house in eleven places) is moving and splitting apart as much as 1/8”+ from each other. No board has cracked. Some have pulled apart on their ends and others side-to-side. Mostly this is happening near or in line with the south bedroom foundation that is sagging. And, the T&G ceiling (2 ¼” thick – same material as the subfloor just flipped over to the pretty side) is ever so slightly, in very few places, splitting apart in the direction of the south bedroom foundation. They run parallel to the south foundation wall as does the wood floor thus the T&G subfloor runs perpendicular to the ceiling T&G, wood floor and foundation south wall.
For the three years we lived in the home the wood floor never moved, even after rains that soaked the south bedroom foundation area, and only it, in the area just outside of it and in the crawlspace (dampened it for two fee around it) – but, the T&G did move and creek a bit for weeks afterward but very little. We know when it does because we caulked between the T&G ceiling and saw evidence of movement by the small tears in the painted Alex caulking.
Question 1 – Foundation Support:
How do we support the south foundation wall? We were thinking of digging 3 1/2 feet down by 2’ wide (under the frost zone) in our hard clay soil and put in ½ foot of stone and a sizable piece of structural steel with a 2 foot x 10” header and with rebar all thru it and then mix-up some cement and pour it in. We thought of doing that at 3 or 4 points along the wall but wonder if we would be creating a situation where we fracture the foundation wall because it’s only supported by the piers we make. We would love your ideas.
Question 2 – Cement in the Winter even a Warm Winter:
At what temperature must the evenings be above to pour cement?
Question 3 – Jacking to Move back and Save the wood Floor:
Once we have stopped the foundation movement how do we jack the foundation and how far can we move it before plumbing, bathroom stone tiles and mirrors break?
We can do the work ourselves! Your help would be greatly appreciated!