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32A-172 (7) Structural Evaluation The Collector Galleries October 20, 2008 The existing upper floor joists are adequate for supporting the required 40 pounds per square foot (psf). Of course, this assumes that they are in good condition. Typically, damage exists in old wood framing around bathrooms. This is due to plumbing leaks as well as excessive notching by plumbers. There may also be other hidden defects that exist as a result of previous remodeling work. There are also other defects that are part of the original construction, such as the misalignment of studs and joists. The existing dividing walls between the upper rooms do not appear to be load bearing, at least in the front section of the "ell ", and they could be removed or relocated in most cases. Although the sizes of the steel beams under the 2n floor are not known, I see no reason to doubt their capacity to support the loads of the floors above. The lines of the soffit appear straight in the 1st floor ceiling at the beam locations. Considering their age, it is also fair to assume that they are adequate. Of course, one or more of the beams could be exposed so that its cross - section dimensions could be accurately measured and its strength calculated. It is extremely beneficial to proceed with the renovation work as a "full gut ". Removal of all ceiling and wall finishes allows for repairs of all types of deficiencies, and not only structural problems, but also shortcomings in the electrical system, plumbing etc. As well, it permits a much more thorough and effective installation of thermal insulation. FURTHER INVESTIGATION Before commencing any renovation work, certain areas that currently are not fully accessible should be probed and explored in more detail. This would help the process of construction cost estimating by reducing unknown conditions. I believe that the extent of the timber truss in the attic, specifically whether it suspends any of the floors below, as well as the supports of the truss itself, should be investigated. Also, the conditions around leaks in the lower, flat roofs should be exposed. This probing involves selective removal of architectural finishes, primarily in the ceilings. This demolition work should be conducted by a contractor or qualified handyman. Ideally it would be the contractor who would be doing the final renovation work. I would observe the probes to inspect the conditions as they are exposed, and to determine if additional probing is required. I would also be available to provide you with structural engineering consulting services in the final design and drawing for the renovation project, as well as during construction. I hope that you find this report satisfactory. Please let me know if you have any questions. Respectfully Submitted, Ryan S. Hellwig Massachusetts Professional Engineer #37300 - STRUCTURAL Page 4 of 4 Structural Evaluation The Collector Galleries October 20, 2008 in the western part of the "ell ". This could be related to the truss in the attic. It is also possible that the sag occurred a long time ago, and that it may have been arrested by the steel beam and column system. The structure of the first floor is almost entirely plastered over in the basement. There are steel pipe columns visible. In one area off of the boiler room, the floor joists are exposed. They are full- dimension 2x10 spaced at 16 inch centers. There is a timber carrying beam under one end of these joists. These joists and beam appear to be in good condition. Some of the structure was inspected in the lower one -story roof, where plaster damage occurred from roofing leaks. There is localized damage to the wood sheathing and also to some of the wood joists from the leaks. Also, it appears that there was an older porch structure in that location, due to the presence of older studs cut off above the current ceiling, and a band joist about 4 feet off of the main exterior building wall. Most of the flat roof joists could not be seen due to the thermal insulation, much of which has fallen down and is therefore ineffective. There are 4" pipe columns supporting the edge of the roof, but the edge beam is not visible. The ceilings of the first floor are plaster on metal lath. Much of the ceiling appears to have been damaged by the water from fighting the recent fire. In some locations, the plaster seems to have come loose from the supports above. The joists of the first floor framing exhibit a small amount of sag, and also bounce underfoot. For the most part the foundation walls are in good structural condition. There is a musty mildew smell in the basement, which is to be expected whenever there is storage of paper and wood -based items. Some water leakage is evident along the east wall in the basement. RENOVATION POTENTIAL With the exception of the roof, the structure is generally in good condition for a building of its age. Of course, the roof could be reinforced in place. However, between the fire damage the thrust problem, the repair work would be extensive, and labor intensive. Another option would be to replace the roof structure with light lumber trusses. They could be designed to bear on the attic floor but with a raised heel that would maintain the current eave line. This way the bent or broken studs could be cut down to the attic floor. Also, the attic joists themselves could be removed, freeing up the 3r floor since the corridor walls would not be required for supporting the attic floor joists. If necessary, a small attic space could be built into these trusses. In converting the upper floor into apartments, the Use Group in terms of the Building Code would continue as Residential, perhaps with a change from R -1 to R -2. Therefore, the required live load capacity would also be unchanged. This is advantageous for the Code review process. Much of the existing building structure, including the first floor would be considered "grandfathered ", if the Use is indeed unchanged and there is no obvious overstress or damage. Full compliance with the live loading requirements of the Code for new construction would not be required. Page 3 of 4 Structural Evaluation The Collector Galleries October 20, 2008 the rafters do not rest on the attic floor, but rather they bear on top of the exterior wall which cantilevers two feet above the attic floor. Because this roof system does not have structural support of the ridge, the rafters are held up in their inclined position in a manner similar to a simple tent. They resist roof and snow loads by pushing against eachother at the central ridge, and consequently they exert horizontal thrusts at the exterior walls. This is typical of conventional light -frame wood construction. But because the rafter ends are raised above the floor, this thrust is not directly resisted by the attic floor joists, but primarily by the cantilevered wall studs. It is obvious that the roof has spread outward on account of this lack of sufficient restraint. The studs are clearly bowing outward. This occurs more noticeably in the middle portions of the walls, because the wall corners inherently provide more thrust resistance, while away from the corners there is less of such resistance. Several studs have cracked and split where the attic joists are nailed onto their sides. There is also one "come- along" with a steel cable from the top of the western wall down to the attic floor, presumably an attempt to fix this problem. There are several non - original studs under the middle of the ridge board, which are probably another old attempt to hold up the sagging peak. The worst condition is at the valley, where the top of the diagonal valley rafter has dropped a few inches, also with a prop underneath, and the lower end appears to have pushed outward. One of the two walls that connects to this valley is severely racked. When looking from outside, the valley is clearly sagging relative to the adjacent roof planes, and the slates appear to be buckled. Typically valleys hold significantly more snow load than hipped ends. There is widespread fire damage to the rafters. In most areas the damage is superficial. However in some locations it appears to extend about 1 /4" below the surface. This represents a significant loss of strength. There is a heavy timber truss with wrought iron rods that supports the rear portion of the roof and attic floor. There are also rods dropping down to below the attic floor, and it may be that these rods suspend the underside of 3 floor, but this cannot be confirmed without poking around in the walls. Also, the supports of the truss could not be determined at this point. In general, the truss itself is in good condition, as compared with the hipped rafter system. Some of the joists under the 3rd floor are visible above the ceiling in the 2 floor bathrooms. They consist of full- dimension 2x8 softwood lumber spaced at 16 inch centers. In general the joists appear to be in sound condition. The exterior walls are balloon - framed. There is a header visible above the bathroom door, and it is the traditional trussed 2x4 type. The stud spacing visible there is not aligned with the floor joists, and there is only a single top plate on the wall. The joists under the 2 floor are visible above the 1 floor ceiling underneath the bathrooms, where some plumbing had to be accessed. They are also 2x8 spaced at 16 inch centers. One joist has been cut almost clean through for a pipe. There is a short piece of 2x4 attached to the side, but that is not adequate. One of these access holes exposes part of one of the main steel carrying beams under the corridor walls. The full size of the beam is not visible. The upper floors have an obvious sag which is noticeable in the corridors. The deflection is most significant Page 2 of 4 3 d 19 • RYAN S. HELLWIG, PE • STRUCTURAL ENGINEER • October 20, 2008 The Collector Galleries 11 Bridge Street Northampton, MA 01060 Attn: Leslie Durkee Re: Structural Evaluation The Collector Galleries' Building 11 Bridge Street Northampton, MA Leslie, The following is a summary of my preliminary evaluation of your building. On October 7, 2008, I personally conducted a visual inspection of the structure. This inspection was limited to all accessible areas of the building where the building frame is exposed, which is primarily in the attic. In most of the first and second floors, the structure is hidden by architectural finishes, such as wall and ceiling plaster. Some of areas in the ceilings of the first and second floors had been previously opened up to expose the plumbing, and some of the structure was visible there. Many of the rooms in the upper floors are padlocked. A follow - up inspection of a couple of holes in the porch roof ceiling on the west side was made on October 20, 2008. GENERAL DESCRIPTION The building is assumed to be approximately 100 years old. The structure is predominantly wood - framed. There are three floors and a full basement. The main part of the original building is rectangular, and is roughly 45 feet by 60 feet in plan. The second and third floors are slightly smaller, having an "ell" shape. The upper roof is hipped, with a valley at the intersection of the "ell ". There is a one -story area all around this main section that is used by the stores on the first floor, which has a flat roof. There are two bearing walls in the front portion of the 2" and 3` floors, supporting the joists on either side of the corridor. In the 1st floor, there are steel beams and pipe columns directly underneath these bearing walls. I assume that these beams and columns are not original to the building, but that originally there were solid interior bearing walls that ran all the way down to the first floor from the attic. I believe that the building was substantially renovated at some time in the past, and that those walls were removed, and the beams and columns installed to support the upper floors while opening up the space, presumably for the retail use. CONDITION ASSESSMENT The portion of the structure that is the most visible is the framing of the upper roof. The common rafters are full- dimension 2x8 spaced at 20 inches on center. The hip and valley rafters are 3x10's. 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