Method Statement for Epoxy Terrazzo Flooring.
PURPOSE AND SCOPE.
This method statement defines the activities and the
sequences which are to be carried out for
the application of Terrazzo works accordance with the requirements
specified in the relevant
specifications, procedures and drawings and the subsequent curing and
protection for Terrazzo work.
This method statement applies to all the Terrazzo work.
Equipment’s
- Mixing Machine
- Mixing Paddle
- Rollers
- Pin-Leveler
- Hand-grinders
- Cutting Grinders
- Grinding Machines
- Diamond tools
- Buffing Machine
- Vacuum
Delivery, Handling and Storage.
The Materials will be delivered in Truck and will be
offloaded with comb lift at site.
Store materials in chemical storage, under cover, and in a
dry location to prevent their deterioration or damage due to moisture,
temperature changes, contaminants, corrosion, and other causes.
The materials (In pallets) will be transferred to floors and
unloaded on loading decks of desired floor and from there will be shifted to
desired places through trolley.
PROCEDURES.
Pre-construction activities/Approvals
Ensure Material/ Shop Drawing/ Mock-up inspection/ MIR has
been approved and properly coordinated to all site team.
Ensure to obtain the approval of Method Statement
Submittal.
Ensure the Materials are stored at the designated storage
area.
First aid and First aid arrangement shall be made available
on the site.
Project Quality Plan to be adhere.
Project HSE plan to be adhere.
Inspection of Vehicle & Operators for Eligibility,
Competency and Safety.
All Clear Safe to Work Procedure to be adhered, ensure
that:
Access Route checked and deemed safe.
Work area checked and deemed safe.
Correct PPE worn by all workers.
Tools and Equipment checked and all safe to operate.
Fire prevention safety measures checked and deemed
safe.
To have PWT where required
Method Statement available and that workshop has been
conducted.
Working area checked against Risk Assessment.
Toolbox Talk conducted.
Training will be provided by the Safety Department to all
persons involved prior to starting works.
Ensure that the work area is clear and safe.
Ensure that HSE & QAQC procedure are established (Plans
are Restricted to only re-mobilization and procedures are from HSE Plan &
Project Quality Plan which will cover all the requirements)
A safety induction shall be provided prior to the start of
the work.
Ensure 5 points PPE are worn at all the times includes hard
hat, coverall or HV vests, safety shoes, hand gloves, safety goggles and task
specific PPE will be worn according to the requirements.
Proper communication to be maintained during the task.
On completion of works, they will be checked by Contractor
Construction & Safety Teams.
When Contractor Construction Teams are satisfied that the
works are completed, they will be
responsible to inform Safety Team for the final inspection and
subsequently to be inspected by the
Engineer / Consultant.
It is the contractor’s Safety Team’s responsibility to
ensure that the work may not commence before the necessary approvals from Consultant &
Client are obtained.
Before storing any material, the area must be inspected by
the HSE Department to check the suitability of the area and confirm whether a
Fire Protection System is needed or not.
If Fire Protection arrangements are required, then the
Safety Manager, MEP Manager and Construction Manager will discuss and arrange
accordingly.
General.
Tools, equipment, and all associated materials to be shifted
to the work location.
Areas where Terrazzo system are to be placed should be
closed, or surrounded by a sufficient protective cordon and fence, this is to
protect the compacted substrate from damage and to avoid rework loops.
Method statement, Risk Assessment of the works to be briefed
to the operative’s prior start of the works.
Only In Out Concepts trained masons shall be engaged for the
strip installation and grinding activities.
Proper PPE requirements for the works shall be ensured.
All the safety requirements and permit to work to be ensured
prior to starting works.
Proper supervision shall be ensured for the whole course of
installation ensuring the work done as
per approved shop drawing with quality standards as per
approved method statement.
Preparation.
At the time of installation of the Terrazzo, the substrate
concrete should have a minimum tensile
strength of 1.5 MPa, be more than 28 – 56 days old as per moisture and
site requirements and the surface should
be dry. Prior to application of the
Terrazzo System, the substrate must be thoroughly surveyed to ensure that it is
sound (above 25N/mm2), dry and of acceptable level and finished to accept a
10mm high quality resin finish. Engineer should have made allowance for any
structural movement by installing the correct movement joints (To be continued
through the Terrazzo System).
The System should not be applied onto any floor substrate
where moisture content exceeds 75% RH (+3% moisture content) – Moisture test
shall be done by using Moisture meter.
Substrate Floor Flatness.
The substrate concrete or
screed should be installed to the following tolerances as per BS 8204-Part 6:
2001 – Table 2 Class- SR1 (±
3mm maximum deviation
from a 3m straightedge laid flat on the substrate) which is required for
the flatness of the finished terrazzo floor. Any repairs to the
substrate or correction of the required flatness etc. should be carried out in
good time prior to the installation of the Terrazzo.
The flatness of the floor substrate is very important for
the subsequent Terrazzo application.
Surface Preparation.
Concrete substrates must be prepared mechanically using
abrasive blast cleaning or scarifying equipment to remove cement laitance and
achieve a profiled open textured surface.
High spots must be removed e.g., grinding.
All dust, loose and friable material must be completely removed from all surfaces before application of the product, preferably by brush and vacuum.
Substrate defects, such as cracks, blow holes and voids (if any) must be repaired using appropriate products.
Note: The selected Method of preparation will depend on the
surface condition environmental
constraints and availability of services.
Dividing Strip Installation.
Metal Dividing strips should be permanently fixed to the
surface of the screed at all “Free Edges” and any isolation / construction /
saw-cut control joints in the floor substrate, at column bases and perimeter walls etc. wherever movement is
expected, including adjacent finishes, metal finishes and at door
thresholds.
For any other required sealed joints, the joints should be
formed by using two of the edging / divider
strips fixed back-to-back to the required width of the joint and
subsequently filled with an appropriate and approved sealant for the end
use.
Inspection for surface preparation.
On completion of the preparation of the applications, that
is when formwork and any built-in items
are fixed. The workmanship will be check by:
1-Contractor Site Engineer
2-QA/AC Engineer
3-Consultant Engineer
Care shall be taken to clear off all debris like pieces of
binding wires, wood, and bits of reinforcement / cut end projecting into the
cover of concrete by using compressed air before pouring materials is
placed.
All the above work prior to application shall be inspected
and approved by the Consultant / Engineers thru Inspection request.
When the Site Engineer is satisfied that the work is
completed and MEP clearance signed by all parties obtained, He will be
responsible for the completion of preparation check list form and the same to
be submitted to Contractor QA/QC Engineer. After checking the QA/QC Engineer
will submit the same to consultant for inspection. Application to be conducted
only after the consultant’s approval.
At a suitable time prior to the Terrazzo pouring, the
foreman will ensure that the necessary plants and equipment are in good running
condition.
It is the Contractor QA/QC Engineer’s responsibility to
ensure that the pour may not commence before the necessary approval from the
Consultant.
Substrate Priming – Sikafloor-161.
Primer:
Mix part A & B components using a slow speed electric
stirrer (300-400 rpm) with adequate mixing paddles for at least one minute.
Pour mixed material into an industrial paint tray and apply by roller, taking
care to avoid ponding. Apply the material around the edges of areas and into
the termination grooves by brush to ensure even spreading at the following
coverage rates.
Make sure that continuous; pore free coat covers the
substrate. Apply sikafloor-161 at a consumption of 0.2 – 0.3 kg/m².
Embedded the crack suppressant Mat into the wet primer and
firmly pressed the mat into the wet primer using a flat trowel.
Primer should be allowed to cure for a minimum of 8 hours
and maximum of 48 hours. The surface must be dry to the touch before
overlaying.
Application of Sikafloor – Terrazzo SA.
Mixing and placing.
Have sufficient, large enough clean containers to allow
mixing of material for a continuous supply to the wet edge, start application
required distance from mixing station and work towards it.
Organize the site with all necessary material for the day’s
activities.
Set up a mixing station for better efficiency and convenient
transport to the placing area.
Do not set up the tool cleaning area near the mixing station
due to risk of contamination of new batches with the cleaner which would affect
the color of the Terrazzo.
Depending on the mixer type, a several containers can be
used for mixing and transport, or a separate wheelbarrow used exclusively for
the transportation process.
Mixing Procedure.
Material and ambient temperature will affect the mixing
process. If necessary, condition the
materials for best use to between 18ºC to 25ºC. Please refer to the
instructions for mixing which appear in each product’s data sheet.
Stir separately components
A and B
of Sikafloor®- Terrazzo
SA well with
an electric mixer, then add
the full kit
of component B
into component A
and mix with a
slow speed mixer (max.
400 rpm) for at least 3 minutes until a homogeneous mixture is achieved.
Place mixed material into a clean Pan Mixer and mix again shortly.
Gradually add part C (aggregate) to the mixed resin and
hardener parts over a period of 15 seconds. DON’T DUMP! Allow part C to blend for a further 2 minutes
minimum, to ensure complete mixing and a uniform moist mix is obtained. During
the operations, scrape down the sides and bottom of the container with a flat
or straight edge trowel at least once (parts A+B+C) to ensure complete
mixing.
Allow the Screed material to stand for a few minutes to
allow entrapped air to escape.
Placing of Sikafloor Terrazzo SA .
Spread all the mixed Component’s A+B+C on to the floor
immediately after mixing and spread by steel trowel to the correct thickness
and strike off flat using the installed divider strips as a guide at the
following coverage around 25 kg/m².
Smaller areas are simply applied from the mixing vessel and
spread to the height of the divider strip by trowel. Work with the pot life of
the material.
Compact the placed material using a wood or plastic
float.
Close and flatten the surface using steel float.
Clean all tools and application equipment with thinner
immediately after use. Hardened and / or cured material can only be removed
mechanically.
Allow to cure for a minimum 16 hours.
Do not apply when atmospheric condensation is occurring or
likely to occur before full cure is attained, i.e., when the dew point is
reached or when the ambient or substrate temperature is within 3°C of the dew
point. Normally full cure is reached after 24 hours, but under very cold or
very dry conditions this may be extended to 48 hours.
Grinding, Grouting and Polishing.
Initial rough grinding
Second rough grinding
Grouting.
Fine Grinding/Polishing
Initial rough grinding
This requires the use of diamond grinder and would also
require an edge grinder for grinding close to adjacent finishes and around
columns etc.
Rough grinding with 24 grit metal bonded abrasives until an
even distribution of the aggregate’s matrix is achieved.
The mobile grinding machines should be fitted with suitable
dust extractors for dry grinding.
Second Rough Grinding
This requires the use of a diamond grinder and would also
require an edge grinder for grinding close to walls, doorways, adjacent
finishes and around columns etc.
This grinding frees the surface from scratches.
Wash down and vacuum the area before commencing the second
rough grinding using 60/80 grit
stones.
After this grinding activities 70% of aggregates should be
revealed and match the submitted samples.
All divide strips should be clearly defined.
Grouting.
Clean Terrazzo floor with clean water, rinse, vacuum and
allow to dry prior to grouting.
Mixing of Sikafloor-169
Stir separately components A and B of Sikafloor®-169 well
with an electric mixer, then add the full contents of component B into
component A and mix with a slow speed Mixer (300 - 400 rpm) for at least 2
minutes until a homogeneous mixture is achieved,
Then add component C bags to the mix and complete mixing for
two more minutes.
Prior to mixing, stir component A (resin) and add all of
component B (Hardener).
Make sure the hardener is fully emptied into the resin
component.
Mix both components thoroughly with a low-speed electric
stirrer(300-400 rpm)
Application –
Sikafloor-169 Grouting.
After allowing Sikafloor® 169 to stand for 3 minutes (allowing entrapped air to escape) start the application of epoxy resin by means of squeegee or wiper. Work the resin into the substrate to ensure all blowholes and grinding etches are filled. Freshly applied Sikafloor® 169 should be protected from DAMP, CONDENSATION AND WATER FOR AT LEAST 12 HOURS. FINE GRINDING MAY COMMENCE AFTER 12 HOURS OF CURING AT 25 DEGREES CELCIUS.
Fine Grinding/polishing.
Grind a wet grind using plastic bond diamond tool, of 150 to
170 grits until all grout is removed from the surface. Wash and Rinse with
clean potable water. This is the final finishing in accordance with NTMA. If
any pinholes are visible at this point repeat the grouting process described in
5.2.7.5, c) Application sikafloor-169 Grouting.
Depending on the surface finish required, plastic bonded
diamond tools grit shall be changed.
After completing fine grinding wash the Sikafloor – Terrazzo
SA with clean water, rinse, vacuum and allow to dry.
Sealer application.
After allowing the Sikafloor-Terrazzo SA to dry commence
with the application of the sealer coat. Mix the Sikafloor 169 as detailed in
5.6, c) Application sikafloor-169 Grouting.
Apply Sikafloor 169 at a rate of 0.12 kg per square meter
this can be done by short pile roller.
Special care should be taken to minimize roller marks.
Allow the final coat of Sikafloor-169 to dry for a minimum
of 12 hours.
See Risk Assessment Template for Epoxy Terrazzo Flooring.
See Checklist Template for Epoxy Terrazzo Flooring.