Having problems with deflection and sagging in the floor and wondering if the joists are simply under-dimensioned. Or if something else is wrong.
The joists are 195X35 and span from foundation wall to concrete beam to foundation wall. A total of 8 meters. On top of the joists is 18 mm tongue-and-groove planking. Between the foundation wall and the concrete beam, there is also a beam on each side with the dimension 150X50. The beams span about 3 meters from pillar to pillar. Measuring on the beams, they are sagged about 1cm in the middle. Which is how much the floor above is sagged as well. I have looked at the joists both from above and below in various places and can't find anything wrong. It looks healthy. Appears healthy when you hit it with. The beams are admittedly brown (like telephone poles). But it seems to be some sort of impregnation or something. It is an LB house with a crawl space built in '65.
Oh, by the way, it's CC 45 between the floor joists.
The joists are 195X35 and span from foundation wall to concrete beam to foundation wall. A total of 8 meters. On top of the joists is 18 mm tongue-and-groove planking. Between the foundation wall and the concrete beam, there is also a beam on each side with the dimension 150X50. The beams span about 3 meters from pillar to pillar. Measuring on the beams, they are sagged about 1cm in the middle. Which is how much the floor above is sagged as well. I have looked at the joists both from above and below in various places and can't find anything wrong. It looks healthy. Appears healthy when you hit it with. The beams are admittedly brown (like telephone poles). But it seems to be some sort of impregnation or something. It is an LB house with a crawl space built in '65.
Oh, by the way, it's CC 45 between the floor joists.
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So, are there two sections each with a 4 meter span? That is, the support in the middle is in the middle of the 8 meter span?
Anyway, 45*195 is rather flimsy for these spans. I had a similar floor at work this week and it required 45*220 in K30 quality with screw-glued 22 mm particleboard to handle the deflection.
Is it newly built? Has someone calculated the floor for you or has the carpenter improvised a bit?
Anyway, 45*195 is rather flimsy for these spans. I had a similar floor at work this week and it required 45*220 in K30 quality with screw-glued 22 mm particleboard to handle the deflection.
Is it newly built? Has someone calculated the floor for you or has the carpenter improvised a bit?
Yes, that's exactly it. The mid-support is in the middle of the 8-meter span. The beams stretch from foundation wall to support beam to mid-support to support beam to foundation wall. Essentially, they span 2 meters between each support. But the support beams are sagging between the piers about 1 cm at the most. The support beams, which are 2X6 inches, rest on piers and span 3 meters between each pier. The floor beams are NOT 45X195. They are just over 32X195. Some inch dimension? In the places where the floor beams run directly over the piers of the support beams, the floor is rigid over the entire 8-meter span. So I'm wondering if it might be that the support beams are perhaps too weak or span too far for the dimension? The house was built in 1965, as mentioned 
I think I understand how it's done. You shouldn't have problems with deformation with these dimensions, but you should never say never. I assume the 150*50 beams are under the 195s? In that case, if you can access your 150 beams, you can use a jack to lift the middle of each 150 beam and then double it with another one of the same length. If you use screw adhesive with fairly thin screws with a total length of about 100 mm, you will double the strength of the underlying beams. This should eliminate most of the flex since the span of the upper ones is not more than two meters.
I assume these two layers are perpendicular to each other?
I assume these two layers are perpendicular to each other?