The boathouse expansion is making great progress. Poor soil has been replaced with gravel or stone to build a strong foundation, and now footers and roadways are being constructed. The footprint of the multi-purpose room (bottom left) and locker rooms (top left) can clearly be seen, as well as the roadway taking shape as indicated in the faint yellow line. Our only surprise was hitting an old foundation wall at top right (photo location 1) which had very minimal impact. Black fabric is being covered with crushed stone to form the drive lane and parking area to the right. Silt fence (parallel black lines at the bottom) will prevent site soil erosion from entering the canal. Inside, the boat racks have been removed and will be replaced this month.
Primary earthwork is being completed by a Cat excavator including digging foundations, grading the site, and removing poor soil and replacing it with stone.
Corner of barn foundation in the parking area. The remaining foundation remains in place. See photo location 1.
Trenches have been dug, leveled with stone, and compacted to form footings that support the weight of the building. Photo location 2.
Once trenches are prepared, wooden forms are installed to form the edges of the poured concrete footings. String lines indicate where the forms should be placed. To the right of the trench the grade abruptly drops down to meet the grade that slopes to the water. A stepped footing will follow the grade change, keeping the foundation below the frost line in winter. Photo location 3.
The column footing in the background is in line with the building footing that separates the locker room wing from the multi-purpose room. Because it is internal to the building, it doesn’t have to go below the frost line. A wood form holds the concrete’s shape. The steel re-bar grid gives the footing tensile strength. The for bolts will anchor the steel column at a future time. The bucket at right contains a pump to de-water the site.
Concrete masonry units (CMUs) are literally the building. At right short 4” tall half height blocks are used on the first course. Rebar slips into pre-drilled holes in the foundation. The “corner block” is a special and when flipped every other course forms a strong corner. The next rows will be full 8” high blocks that are 12” wide.
A. Batter boards outside the work zone create a fixed point for string lines
B. Mortar is a blend of cement, lime, sand, and water
C. A concrete mixer blends the mortar that will be troweled between blocks to bind them together
D. Both rebar and concrete blocks are cut as required with a masonry cut off saw
E. Pairs of re-bar are inserted into block cavities which will then be filled with grout to add vertical rigidity to the foundation wall
F. A metal lattice is laid right to left along the entire block course and embedded in mortar before setting the next row of blocks. This lattice provides horizontal rigidity to the wall.
G. Concrete will be poured around this rebar frame to form piers for the window wall framing