Structural Engineering Report_ House Relocation

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C/- Graeme Jones                                                                                Page 2 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                         Ref. No. 2020.0128




STRUCTURE

The existing house is a low set timber building that is understood to be pre-war and constructed at least
100 years ago. The building is of timber construction with pine linings constructed on a hardwood
frame. The building is clad in chamferboard and metal roofing. A separate garage structure sits
adjacent to the existing house and is of similar construction to the main house.




Figure 2, Front, Rear and Separate Garage

The building is of rectangular form with what appears to be a “non-original” back veranda and laundry to
the rear. The sleepout and bathroom / pantry appear to be an early addition (approximate date to be
confirmed by Heritage Consultant). The sunroom and front veranda appear to be part of the original
construction that has been enclosed.




Figure 3, Floor Plan

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C/- Graeme Jones                                                                               Page 3 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                        Ref. No. 2020.0128




Cladding
The chamferboard appeared to be in relatively sound condition given its age. There was typically no
evidence of insect damage or rot at key locations where such damage would normally be evident (eg at
window edges and building corners likely exposed to pooling water). There was widespread minor
defects to the chamferboards including visible damage, paint flaking, discolouration and rust stains
around nail heads.




Figure 4, Chamferboards cladding

Window framing
The window framing inspected appears to be in reasonable structural condition without visible evidence
of water damage (rot). The frames have not been maintained recently and as such the timber is
partially exposed to the elements without paint protection. Despite this, the hardwood frames appear to
be in reasonable condition.




Figure 5, Hardwood timber frames

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C/- Graeme Jones                                                                                 Page 4 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                          Ref. No. 2020.0128




Foundations
The existing residence is founded on concrete blockwork stumps. Two sides of the existing building
(front and sunroom side) are sitting on breezeblock blockwork perimeter walls. It is unlikely that the
foundations formed part of the original foundation system and are likely more recent.




Figure 6, Concrete blockwork stump foundations

During the inspection, it was noted that some foundation settlement appears to have taken place,
resulting in door and window frames that were not square and some areas of floor that were not level.
As the building is proposed for relocation onto new foundations, the condition of the existing foundations
has not been the subject of this report.
It is expected that the floor can be re-leveled on new foundations on relocation.

Floor framing
The hardwood timber floor framing comprises bearers and joists supported on concrete blockwork
stumps. The framing adopted appears to be logical and well-constructed.
Some of the timber framing members show evidence of weathering, however this appears to be
superficial only with a sound timber core remaining. Localised bearing areas around concrete stumps
are often locations where water accumulates causing timber softening and rot, however no evidence of
significant timber degradation or softening was identified during the visual inspection.




Figure 7, Timber floor framing condition

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C/- Graeme Jones                                                                                Page 5 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                         Ref. No. 2020.0128




Rear Veranda and Laundry
The built-in rear veranda and laundry appears to be “non-original”. This construction does not appear to
reflect the same quality of workmanship or materials as the core original structure. There is evidence of
water damage to the external chamferboard cladding and damage to the window framing. The timber
floorboards to the rear veranda are unsealed and in poor condition.
It is anticipated that these “non-original” building elements may be removed or reconstructed in the
relocated dwelling.




Figure 8, Rear veranda




Figure 9, Laundry extension

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C/- Graeme Jones                                                                                Page 6 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                         Ref. No. 2020.0128




Internal structure
The internal structure appeared to be in relatively sound condition with the exception of the bathroom;
which showed noticeable signs of damage locally around the wet areas. Tops of floorboards were
painted and visible with no floor coverings. The floorboards showed signs of general wear and tear
typically. Some localised areas of flooring have been replaced and left unpainted. The underside of the
original flooring appeared to be in relatively good condition when inspected from the sub-floor.
The bathroom wet areas have exposed floorboards and appears to be an early addition to the original
house (~1920’s – to be confirmed by Heritage Consultant). Wet areas typically have a useful life
considerably less than that of the home as whole. Bathroom renovations after 20 years of useful life
typically require replacement of the entire bathroom including wall sheeting, waterproofing and tiling.




Figure 10, Timber flooring, Hallway and Bathroom

VJ internal wall cladding appears to be generally in good condition. However, there is some evidence of
building movement causing the door and window framing in Bedroom 1 to appear slightly out of skew.
This level of movement is not considered structurally significant.




Figure 11, Bedroom 1, Door and Internal Window, Veejay joint opening

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C/- Graeme Jones                                                                                Page 7 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                         Ref. No. 2020.0128




Roof structure
The roof cavity was not able to be accessed during the inspection due to unknown asbestos condition
and tall ceilings making it potentially unsafe. There was no visual evidence of internal water damage
from roof leaks. The condition of the rafters cannot be described with any degree of confidence.

Garage
A separate timber framed garage structure sits adjacent to the existing house and is of similar
construction. The garage was locked and inaccessible during our site inspection. From external
inspection, the garage structure is in significantly worse condition than the existing house. The
chamferboard cladding is weathered and damaged (rotted) typically, with boards missing in some
places.




Figure 12, Garage, External

The floor framing is obviously sagging and appears to be lacking critical load bearing support through
the centre of the floor framing. Cut-off tree stumps were visible underneath and appear to have been
aligned purposefully with the central floor bearers. These may have been positioned to support the
central bearer, however there is an approx. 100mm gap between the top of the stump and the bearer. In
any case, cut-off tree stumps are not a suitable foundation alternative to a concrete or blockwork stump.
Timber floorboards are in poor condition and timber joists and bearers have split in several locations,
possibly due to being over-stressed. Poor quality remediation measures to some joists (splice timbers)
have also been installed.

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C/- Graeme Jones                                                                                  Page 8 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                           Ref. No. 2020.0128




Figure 13, Garage, Sub Floor Framing


CONCLUSION

The inspection undertaken was visual in nature and has allowed assessment of visible structure only. It
is possible that structural defects exist that have not been identified in this report, however the visible
original structure appears to have been constructed using quality timber and workmanship resulting in a
dwelling that has weathered well.
There were no visible structural concerns that would preclude a continued use of the building. The
seemingly sound condition of the hardwood framing of the house would mean that the house can be
relocated to a new site provided the correct preparation was undertaken by a qualified and experienced
house removal contractor. A detailed inspection of roofing and framing should be undertaken when the
house is relocated to the alternate site. It is possible that internal damage may be identified once
existing roof sheets and cladding are removed during relocation exercises. A sufficient contingency
should be allowed in the budget for potential timber repair works.
Consideration should be given to the viability of the “non-original” veranda and laundry extension in the
relocated structure, as these do not appear to reflect a similar high standard of construction as is
evident in the original structure.
The separate garage structure is in poor condition and if it is to be relocated, it would need significant
strengthening/replacement of the floor framing and rectification of the chamferboard cladding and
flooring. The internal structure and roofing would also require inspection to determine if these elements
also require rectification.


GENERAL DWELLING RELOCATION RECOMMENDATIONS
The following summarises some general house relocation notes and recommendations based on
previous house relocation experience:
•   The dwelling is approximately 13m wide. A single shift is likely not possible and the house may be
    split down the middle (at least). This ultimately depends on where the house is going and the widths
    of streets and corners on the route. The removalist can confirm once proposed site is identified.
•   If the existing roof is too high to transport, the house removalist will remove existing roof sheeting
    and lower the roof (mark and disassemble rafters flat). The gable end will also be lowered flat. Any
    rectification of the roof structure can also be carried out at this stage.
•   It is possible to keep the original (heritage) elements of the dwelling but demolish the non-original
    extensions/renovations (rear veranda and laundry). The house removalist should be able to do this
    as part of their scope.

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C/- Graeme Jones                                                                                   Page 9 of 9
Structural Assessment – 45 Maple St Cooroy House Relocation
24 February 2020                                                                            Ref. No. 2020.0128




•   The dwelling owner will need to ensure that all asbestos is removed from the house or advise if the
    house contains any asbestos to allow the house removalist to remove as part of their scope.
•   The house removalist will typically provide steel lifting beams that run full width of the house or
    house split. The house will be lifted via jacks to allow the trailer to be positioned under the
    house. They may need to “walk” the house across from site if too close to a boundary to give them
    more space. The house removalist will have a steerable trailer allowing fine movement.
•   There will need to be a number of approvals sought and granted for the removal. The below is a
    summary but not an exhaustive list. A house removalist specialist can confirm any additional
    requirements:
         o    Removal approvals will need to be obtained by the dwelling owner.
         o    Transport approvals typically will be obtained the house removalist, including coordination
              with different government agencies.
         o    Building approvals at new location will need to be obtained by the dwelling owner.
         o    The dwelling owner will need to organise a cut off / disconnection of existing services
              (power/gas/Telstra/water/sewer/payTV) prior to the house removalist coming to site.
         o    The dwelling owner will also need to arrange to remove front fence, landscaping at front
              and existing trees on footpath prior to the house removalist coming to site.
         o    The dwelling owner will need to coordinate with neighbours to advise them of the proposed
              activities.
         o    The dwelling owner should allow at least a month to organise transport approvals with extra
              time for other removal approval and building approvals.
         o    The dwelling owner is required to be covered for “building in transit” insurance.
         o    Removal will occur at night and the house removalist will provide all necessary traffic
              control.
•   Timeframes typically include 1 week at original site for preparation for removal, 1 week at new site
    setting the new dwelling in place.
Should you have any questions or require further clarifications of this report, please do not hesitate to
contact the undersigned.
Yours faithfully,




Leigh Ives
Principal Structural Engineer
BLIGH TANNER PTY LTD