Carnation Walling - Ceiling Beams
Implement the wood beams onto which the flooring block will sit.
Support for the ceiling beams
The reason this is done earlier than you might expect is that we want to get to a rain-proof enclosure as soon as possible so it is more pleasant to work and the materials stay dry.
The 12" thick EPS blocks that form the concrete flooring are supported by 10.5 inch tall wood beams that are in turn supported by 2x6 lumber (1.5" x 5.5"). The 2x6s are supported by a horizontal 2x8 baton that attaches at the top of the vertical 2x4 batons on the north and south walls.
If you have internal divider wooden walls you can implement the studding for these early and incorporate them into the mechanism for supporting the floor during the wet concrete pour.
Make 2x8 batons
TThese may have already been made earlier when making the other internal horizontal bracing.
You want these to be as long as possible so that less vertical 2x4 batons are needed to support them. The hole drilling pattern is as per the 2x4 horizontal braces. The holes are 5-1/2" from the top edge.
They are needed for both the north and south walls and the east and west walls. Also on the tops of internal concrete walls.
Here's the 8" cavity version.../p>
<Update drawing to use 1" from end holes>
And here's the 12" cavity version...
<Update drawing to use 1" from end holes>
TThe actual lengths depend on the length of the wall section and available lumber so you can shorten the lengths in 1 foot increments as required (cutting 6" from hole positions).
Here is the special short beam for the very simple potting shed building (described above). It uses one beam to go the complete width of the building even though that means the hole pattern changes as it crosses the halfway point.../p>
<Update drawing to use 1" from end holes>
For large buildings a center piece to span the building center discontinuity is required.
Fit horizontal 2x8 at the wall
The 2x8 on the north and south walls (run east-west) are for supporting the 2x6s that then support the ceiling beams. 2x8s are also used on the east and west (run north-south) walls so that with 2x6 padding they support the ends of the ceiling beams.
Add a few vertical 2x4 batons on the north and south walls in their final position, but not too many or they will get in the way of the rebar. Do not put them anywhere that will interfere with the windows and doors. Where possible put the vertical 2x4 batons in the wall corners. Attach the horizontal 2x8s at the top of the vertical 2x4 batons using the X'3" holes and 3/8" threaded rod wall ties. Also add the 2x8 horizontal beams on both sides of the internal walls.
It is ok to have a few gaps between the planks if they are not in strategic places.
Frame full height internal walls
Where there are internal walls, these can be framed now in order to reduce the number of ceiling support 2x6s required (north south internal walls) and ideally eliminate any additional props required (east west internal walls).
In the case of my basement the height of the top of the top plate of the internal wall from the slab design height is as follows:
For walls that go north south: 13' 8-1/2" + 5-1/2" = 14'2". This takes it to the height to the bottom of the east west ceiling beams.
For walls that go east west that are not under a beam: 14' X".
The first step for implementing an internal wood wall is to implement a U shaped base to accept the bottom of the vertical studs and hold them in the right place. You can think of the outside pieces of the U being the first bits of wood cladding on the wall.
Make the U pieces to correspond with the internal wood walls shown on your CAD drawing. You will likely need gaps in the Us to avoid the 45 degree wall bracing and other obstacles. Use 2.5" nails to fix the U pieces in the right locations (use a .27 cabiber gun).
I plan the positions of the vertical studs such that they are half way (ie 6") between the primary and secondary concrete wall locations. Every 2' is a sensible distance between vertical studs given that I will eventually be using 1.5" thick wood to clad the walls. You may have to leave out some of the verticals at this stage to avoid obstacles and provide access.
Note that the "slab design height" will have previously been determined by the point on the uneven concrete height adjacent to the outer concrete walls that is the highest. This point was established when building the polystyrene walls. Using the same measuring stick as previously used and your self leveling laser positioned as per previously, determine the height of shim that is needed under each vertical stud to bring it up to the required height. The shims go in the U's so you need to adjust for the extra 1.5" of height provided by the U's.
Fit the vertical studs in the specified locations on the appropriate shims. Make 2x4 horizontals to hold the vertical studs the exact right distance apart as per the locations shown on your CAD drawings. Use pen marks on the horizontals to indicate where the edges of the verticals should be.
Internal concrete wall openings
Where there is a designed in hole in a concrete internal wall that is actually going to be filled in by wooden internal walling then this internal wall can also be framed at this time as it will be used to support the wet concrete of the wall.
Checking building vertical-ness
Make 2x4 ceiling props (If needed)
Make the long 2x4 props that will support the 2x6s. If you don't have 2x4s that are that long then use two pieces and join them.
<Check length shown in drawing>
Make the angled 2x4s that hold the props vertical.
Fit a metal Simpson tie (beam above) to the top of the prop.
Fit the props
The prop positions are shown on the CAD drawing.
Use 1.5" x 1.5" x 3.5" blocks at the bottom on both sides of the prop so that the shims can be kept in place.
Screw the blocks onto the nailed down boards, but do not yet screw the blocks to the vertical props.
At the center of the building there is probably not a 2x4 for the angled bracing so you will need to put a 1' length of 2x4 to the slab under where the prop will be.
Use shims under the vertical props to adjust the height to get everything level. As for the internal wooden walls, use the self leveling laser to indicate the accurate height above the "slab design height". You will need to fine tweak the shims once the rest of the floor structure is in place (and things have settled).
If there is a high spot on the concrete slab that is higher than any high points adjacent to the outer concrete walls then you may need to trim a bit off the length of the prop. If in doubt, trim it to be overly short and then shim it up as needed.
Install the vertical props together with their angle pieces. Do not yet screw the props at the bottom. You need a prop about every 4 or 6 feet along the wall and every 8 feet in the other dimension.
Implement a platform of 2x6s supported by 2x4s (as needed)
The job of the 2x6s is to spread out the function of the props that come up from the floor. They also handle the fact that there are openings in the floor (eg for stairs).
Make the 2x6 horizontal beams. The 2x6 beams only go North-South on the building. The length is variable to suit the building. They don't need to be the full length of the span as long as they span multiple props. No pre-drilling of the 2x6s is required because small wood blocks will be screwed on the top edge later to constrain the beams above. This method avoids leaving screw hole marks in the finished beams.
You DO want the beams (and their associated props) over the floor cutout areas.
Fix the 2x6 lumber on top by slotting into the metal Simpson tie and once the prop is vertical add some 1-1/4" screws. At the wall end, the 2x6 needs to be (for an 8" cavity wall) 8-3/4" from the inside edge of the EPS. For a 12" cavity it is 1' 0-3/4". For an internal wall there is no EPS but the distance from the end of one beam to the end of another on the other side is 9-1/2".
As a further strengthening mechanism if it is felt necessary you can add short lengths of 2x6 between the 2x6 beams to stop them twisting. The length of these is 1' 10-1/2" and they are screwed on offset from each other.
The following shows the horizontal 2x6s from end on (for an example very simple building) (and it is overly supported)...
The number of 2x6 beams and the distance between them depends on a judgment about how much support the ceiling beams above require.
Mark beam positions on top edge of 2x6s
From your CAD drawings, draw marks to show where the beams should cross the 2x6s.
Make 10.5" floor beams
These beams will go into the slots in the EPS Carnation Flooring blocks. They go East-West on the building. They are 10.5" tall and 3" wide formed from two beams that are 5.5" tall and 3" wide. After gluing the beams they are trimmed on a table saw to 10.5". The reason it is ok to use two 5.5" beams is that only the bottom 5.5" of the 10.5" beam will be visible in the finished ceiling. I use doug-fir timber cut on my saw mill for the bottom of the beam. The timber is sawn fresh from the tree so the beam will shrink in width and height as it dries. On the sawmill the beam is cut to be 3+" width and 5-1/2+" where the plus denotes an extra 1/16th of an inch. After drying the expectation is that the beam will be about 3-" and 5-1/2-" where the minus denotes a 1/16".
I glue two 2x6s on top of the sawmill cut beam to form a home-made glu-lam beam.
The overall height of the formed 11" tall beam will be about 10-7/8" (or even 10-3/4"). The glued beam is then cut skillsaw in a custom jig to be 10.5" (cutting the paired purchased 2x6s).
(Alternatively they can consist of a 3" wide piece of 2-by at the top and a 9-1/2" beam below. The 9-1/2" beam can be 2-by lumber or can be a TJI-110 I-beam. You can even make the 9-1/2" beam from 8" lumber with a trimmed 2x4 screwed on the bottom. Cut the 3" x 1" lumber. Screw it to the 9.5" beams.)
If using purchased 2-by lumber then it will likely be necessary to join lengths of lumber to get the required span length. That is the reason that the slot in the Carnation Flooring profile EPS is 3" wide (2 x 1.5"). Joined pieces are offset either side of the available 3".
Here is the process for making the home=made glu-lam beams that I use...
Here is the skillsaw custom jig used to cut the beams to be 10.5" tall...
As the 10.5" beams stay in place for ever and often are visible, I paint them with clear wood protection . Apply with plenty of ventilation to get rid of the VOCs, but it does not contain particularly bad ingredients so it is ok to use internally once it is dry.
Fix locator blocks to the ends of the beams ready for hooking over the support lumber that is at the top of the walls.
Cut the beams so they do not go over the floor openings. Special stepped ends are needed to form the concrete lip.
For my basement here are the lengths and quantilies...
17' 11-5/8" 4
17' 2-1/2" 9
16" 10-1/2" 21
15' 5-5/8" 1
10' 3-3/4" 3
Where there is an opening in the concrete (eg for stairs or elevator shaft) you need to form a 6" concrete lip round the hole. To help with this, the wood beams are a bit different on the end.
Install 10.5" floor beams
The beams go East-West. They extend all the way to the plywood (face of the 1/2 construction plywood closest to the inside of the building). They over-lap the vertical 2x4 batons (and the 2x8 horizontal batons) and are supported by them. Their length comes from the house CAD drawing. The position of the beams is indicated by the marks on the top edge of the 2x6s at the top of the concrete walls. If needed to take out warp in the beams, screw on 1.5" wood blocks to the top edge of the 2x6s that are on the top of the internal wood divider walls. In practice the EPS flooring blocks will likely be sufficient to take out any bow in the beams.
You do not want the beams over the floor cutout areas.
Lag bolts to connect concrete to beams (if wanted)
Once the concrete has been poured and the props have been removed there is a danger that the wood beams could sag over a period of years. To prevent this it can be good to lock together the concrete floor with the beams underneith. This is also added safety in the case of a massive earthquake. The locking together is done using 12" 3/8" lag bolts with 1.5" washers at the head that are installed from above before the concrete is poured. The washers are glued (with PL-Premium) to the bolt heads to stop them dropping down before the concrete is poured. Use about 5 lag bolts per beam. Obviously they need to be positioned in the EPS above the beams. This is the center and edges of the EPS flooring blocks. Alternate 1" from each edge of the beam to catch the 2x6s rather than the join between the 2x6s.
Check the building is square and the walls are vertical by observing the 4 plumb bobs on each of the 4 walls.