13/12/2016
Flat 1, 126 St George’s Ave
N7 0AH
Method Statement
Excavation, underpinning and formation of retaining walls
Flat 1, 126 St George’s Ave, N7 0AH
Dear Sirs,
Further to your request for a Structural Method Statement, please find below our
proposals in principal for the required excavation works being carried out at the above
address. However, please also note that this method statement is to be read in
conjunction with the necessary structural engineer’s drawings and specification which are
still yet to be confirmed.
The existing flanking property will be underpinned in the usual 1 to 5 underpinning
sequence. A standard construction sequence of a typical underpin detail is to be
confirmed by an appointed structural engineer.
This proposed method of construction, reduces the amount of potential ground
movement and so minimizes the effects of settlement to the adjacent structures.
SCOPE OF WORKS
Excavation and underpinning to the existing party walls between No. 126 St George’s Ave
and the adjoining properties as required.
1. EXCAVATION AND UNDERPINNING PARTY WALL FOOTINGS
• Excavate footing by hand in numerical hit and miss sequence as set out in
structural engineer’s drawing details TBC.
• Underpin section to be no more than 1000mm in length, 300mm below existing
concrete footing, and to be 1045mm in total width as per structural’s engineer’s
drawing details TBC.
• Apply dry packing between newly poured concrete and existing footings. Allow
24 hours between pouring of concrete and dry packing.
• No more than 2No pits can be excavated at any one time.
• Allow for installation shuttering ply to up hold the side of the excavated trench,
ahead of pouring concrete.
• Pour concrete, concrete mix as per Structural Engineer’s detail.
• Allow 48 hour drying time to poured underpinning, before excavating the next
underpin in sequence.
• Ensure that no two underpin sections are to be excavated together.
• The next underpin section should be a minimum of 2000mm in distance from
newly poured concrete underpin.
• If at any time cracking appears more than 10mm width in the existing foundation
or walls, then all works are to stop immediately and the Structural engineer is to
be notified as a matter of urgency. The contactor is to take all steps to prop the
section of exposed footings.
2. EXCAVATION AND INSTALLTION OF RETAINING WALL ALONG BOUNDARY LINE
• Excavate footing by hand in numerical hit and miss sequence as set out in
structural engineer’s drawing details TBC.
• No more than 2No pits can be excavated at any one time.
• Allow for installation shuttering ply to up hold the side of the excavated trench,
ahead of pouring concrete.
• Pour concrete, concrete mix as per Structural Engineer’s detail.
• Allow 48 hour drying time to poured underpinning, before excavating the next
underpin in sequence.
• Ensure that no two underpin sections are to be excavated together.
• The next underpin section should be a minimum of 2000mm in distance from
newly poured section of concrete retaining wall.
• Once party walls have been underpinned and retaining walls have been
completed, then and only then can the oversite can be excavated.
POTENTIAL IMPACT ON EXISTING AND SURROUNDING UTILITIES, INFRASTRUCTURE
AND MAN – MADE CAVITIES
Any local services to the property will be maintained during construction and re – routed
if necessary. The exact location of these services will not be known until the works
commence. However, the impact will be negligible as these services will be maintained. If
it is necessary to relocate or divert any utilities, the Contractor and Design Team will be
under a statutory obligation to notify the utility owner prior to any works. This will be so
that they can assess the impact of the works and grant or refuse their approval. There is
no known man – made cavities.
POTENTIAL IMPACT ON DRAINAGE, SEWAGE, SURFACE AND GROUND WATER LEVELS
AND FLOWS All
Existing drainage and sewage connections will be maintained throughout the
construction, works so there will be no impact on these existing systems.
POTENTIAL IMPACT ON EXISTING AND PROPOSED TREES
No existing trees will be felled during the construction of the proposed works. In addition,
there are no trees protected by Tree Preservation Orders in the vicinity of the proposed
works that will be damaged by the construction works.
Please contact me if you require further information.
Director A M Campbell - On behalf of Bluelime
14/12/2016
