Multifamily Apartment: Ceiling tiles are falling from ceiling?
Setting: Waldo County in Unity, ME
This was an multi-apartment unit my brother was living in recently and he was evacuated from after his landlord was made aware of ceiling tiles falling off track in one of the units.
Structural Issue:
In one apartment there was a report that ceiling tiles were “falling down from the ceiling.” The season was winter and there was over 2 feet of snow on the roof. The tiles they were referring to are the 2’-0 by 2’-0 sometimes made of fiberglass or fiber tiles that hang on tracks in suspended ceiling assemblies. Turns out, the plywood that was attached above that ceiling was bowing down and moving the ceiling tiles. The load path was transferring down through to the inside of the structure putting tension in the plywood. The roof construction is composed of trusses so in this photo below what you are seeing is the bottom chords of the trusses, that the plywood is screwed to, are deflecting due to overloading or failure to distribute the load to the exterior walls.
On the exterior of the structure it was clear that the top chords of the trusses had failed, you can see in the photos that there is a depression in the metal roofing. The top chords of the truss are now under or in tension because they are being pulled inward.
According to alpine engineering products the spacing for trusses exactly like these can not go more than 2'-0 on center.
http://www.locketruss.com/roofspan.pdf
By the IRC Code R502.11.1 and R802.10.2- Wood trusses shall be designed in accordance with accepted engineering practice.
 Source: http://tectonicablog.com/?p=82090 |
| Waddell A Truss Design |
Work Proposal: Replace the Roof Assembly
 |
| Source :http://www.arrowheadboomandcrane.com/services.htm |
Conclusion:
I do believe that fixing this structural issue is important enough to justify the cost. I have calculated its going to cost $25,000+ to replace the roof trusses with the proper amount and reconstruct the rental units back. Now, if you wanted to get nit-picky over the replacement cost, one could argue that the trusses that were in-tact could be salvaged and used in the new roof system. Not a terrible idea if we ignored limit state concepts that define when a structural system is engineered properly, it should be able to withstand a localized failure without progressive collapse. Which is what is happening in the case of the apartment unit. Each truss has now exceeded its load-carrying capacity for a long time compromising the structural integrity of each truss.
Resulting in one truss pulling away from the top chords then the next one and the next one. The whole roof was pushed beyond its limit state. So replacing just the damaged trusses is not an option. The roof needs to be replaced and most likely it needed more trusses. Once one truss exceeded its load-carrying capacity that resulted in the eventual progressive collapse of the entire truss system many years after it was built.
Is this a job I would take on? :
I would not take this job on, I do not carry the man power or the insurance currently to de-construct and re-construct this multifamily unit in any reasonable time frame. Also I feel the building owners may contest the roof replacement proposal and if they do then I do not want any part of anything less than that because its to much liability and risk to leave the roof and attempt to just repair the truss.
| Roof Assembly Replacment | ||||||
| Item | Description | Qty | Unit Cost | U/M | Extended Cost | |
| 1 | Roof Truss | T40 2x6 TC 2x6 BC Waddell A Truss | 48 | $ 127.70 | Pc. | $ 6,129.60 |
| 2 | Perlins | 2"x4"x 16' KD Spruce | 138 | $ 8.88 | Pc. | $ 1,225.44 |
| 3 | Metal Roofing | $ - | ||||
| 4 | Soffits | Solid Vinyl Soffit Panels 10"x12' | 20 | $ 9.99 | Pc. | $ 199.80 |
| 5 | Facia | 1"x8"x 10' #2 Pine | 20 | $ 14.15 | Pc. | $ 283.00 |
| 6 | Plywood Ceiling | 4'x8' Plywood OSB 1/2" | ||||
| 7 | Insulation | $ - | ||||
| 8 | Truss Ties | Simpson 18 Gauge Hurrican Tie | 200 | $ 2.44 | Pc. | $ 488.00 |
| 9 | Laterial Bracing | 2"x4"x 16' KD Spruce | 21 | $ 8.88 | Pc. | $ 186.48 |
| 10 | Ceiling Tracks | $ - | ||||
| 11 | Ceiling Tiles | $ - | ||||
| 12 | Disposal Fees | $ - | ||||
| 13 | Rental Fees | Crane Rental Fees | 2 | $ 250.00 | Day Rental | $ 500.00 |
| 14 | Metal Roof Screws | #12 Replacement Screw Metal to Wood- Bag of 250 | 10 | $ 21.19 | $ 211.90 | |
| 15 | Truss Nails | #8 x 3 1/2" 16D Bright Steel Common- 30lbs pack | 1 | $ 32.96 | $ 32.96 | |
| 16 | Fasica Nails | Wood Ring Shank Nails Stainless 2 1/2"- 5lbs Box | 2 | $ 30.41 | $ 60.82 | |
| 17 | Soffit Nails | Grip-Rite Nails 1-1/2" Aluminum Nail- 1lbs Box | 8 | $ 5.76 | $ 46.08 | |
| 18 | Plywood Ceiling Skrews | GRK #9 x 1 1/2" Handy Pack- 100 Pc. Box | 20 | $ 6.80 | $ 136.00 | |
| 19 | $ - | |||||
| 20 | $ - | |||||
| 21 | $ - | |||||
| 22 | Total | $ 9,500.08 | ||||
| Notes per line item: | ||||||
| 1 | 100 / 2 = 50 Trusses - 2 for the gable ends which wont be removed | |||||
| 2 | Perlins are 2' apart perpendicular to trusses which have 22' line length / 2'-0 = 11 Rows(100) = 1100Lf / 16' (2x4s) =68.75 pcs. (x2 both sides) | |||||
| 3 | Can be saved from previous roof | |||||
| 4 | ||||||
| 5 | ||||||
| 6 | The plywood was saved | |||||
| 7 | The insulation was salvagable unfaced pink fiberglass | |||||
| 8 | ||||||
| 9 | 100' building/ 16' (2x4x16)=6.25 pcs per lateral brace assembly. Multiple that by 3, one row for each 2 inner webs and the kingpost. | |||||
| 10 | Can be saved from previous ceiling | |||||
| 11 | Can be saved from previous Ceiling | |||||
| Labor | ||||||
| # of Days | # Of Workers | Total MnHrs | Rate $ / hr | Total Labor | ||
| 15 | 4 Carpenters (8hr days x 5days x 3 weeks) | 480 | $ 20.00 | $ 9,600.00 | ||
| 2 | 1 Crane Opertator (2 days) | 16 | $ 27.00 | $ 432.00 | ||
| Project Total | $ 19,532.08 | |||||
It seems as though this project could be a liability down the road if your proposal was modified or compromised in any way. Good Call
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