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Dovetailed sheets
How do I apply the dovetailed sheets?
On supporting beams: Place the sheets with the profile right-angled onto the beams. The sheets overlay with each other on the position of the beams approximately 50-100mm.
On floorboards: Place the sheets with the profile right-angled onto the floor supporting beams. This means the long side of the sheet parallel to the floorboards. The sheets overlay with each other on random positions approximately 50-100mm.
How do I fit the sheets into each other?
Latitudinal: Only the end lip of the sheets are overlaid. Use the application pointer on the lip: Colour onto colour / metal onto metal.
Lengthwise: Position the sheets alternating with the brand sticker on top and turned to the bottom side. Use the application pointer on the lip: Colour onto colour / metal onto metal.
The sheet with the brand sticker on top overlays over the sheet with the brand sticker turned to the bottom side.
Which lengths are available and are most economic for me?
When used on supporting beams only, it is most economic to use a sheet length which corresponds to a plural of the distance between beams added with 100mm extra for overlay.
1300mm; 2 x 600mm + 100mm. 1600mm; 3 x 500mm + 100mm.
1900mm; 3 x 600mm + 100mm. 2200mm; 3 x 700mm + 100mm.
In case of less standard supporting beam inner distance, “made to measure” length from 0.30m up to 7.00m can be manufactured in our production.
How much do the sheets overlay lengthwise and Latitudinal?
On supporting beams the sheets overlay lengthwise with each other on the position of the beams approximately 50-100mm.
On floorboards the sheets overlay lengthwise with each other on random positions approximately 50-100mm.
Latitudinal only the end lip of the sheets are overlaid. Use the application pointer on the lip: Colour onto colour / metal onto metal.
How do I know if the supporting beams are strong enough for this floor?
Based on the size of the beams, the distance between the beams and the length they have to bridge, Duofor determines if this construction is suitable for the application.
Apart from the above, following additional information is required:
- Which type of ceiling is used under the supporting beams?
- Are there any room dividing walls planned on the floor?
- What is the expected operational load of the floor (house, office, etc)?
- What is the planned size (thickness) of the total dovetailed sheet floor?
- What will be the floor finishing (tiles, terrazzo, carpet, etc)?
How do I shorten the sheets or make excisions?
For shortening or making holes and excisions use an angle grinder with a metal cutting disk.
The inner distance between supporting beams is over 60cm, is that a possible?
Yes, Duofor dovetailed sheets can bridge more that 60cm easily.
You can apply approximately 35mm wet mortar on to sheets which bridge a distance of 1.20m without additional support. This also applies for sheets which are not fastened to the beams.
When fastened to the supporting beams you can apply approximately 55mm wet mortar on to sheets which bridge a distance of 1.50m without additional support.
Do I have to support the plates during application of the mortar/concrete?
You can apply approximately 35mm wet mortar on to sheets which bridge a distance of 1.20m without additional support. This also applies for sheets which are not fastened to the beams.
When fastened to the supporting beams you can apply approximately 55mm wet mortar on to sheets which bridge a distance of 1.50m without additional support.
Do I have to fasten the sheets to the supporting beams?
It is advisable to use only nails to fasten the sheets to the beams. The nails are put into the top notches of the sheet. Three nails over the width of the sheet is sufficient.
In this way the floor becomes more rigid and possible shrinking of the beams is considered.
When applied in combination with floor heating less nails (two over the sheet width) are advised.
Do I always fasten the dovetailed sheets to the supporting construction?
With exception of a noise insulating floor, the dovetailed sheets can be fastened.
How much mortar must be applied onto the dovetailed sheet?
Standard housing residence 20mm on top of the profile (total floor size 36mm)
Offices and shops 34mm (floor size 50mm)
Noise insulating floor 34mm (floor size 50mm)
With floor heating 40mm (floor size 56mm)
With bridging distances over 1.50m 54mm or more (floor size 70mm or more)
Can I apply floor mortar onto the dovetailed sheet?
Yes, Duofor dovetailed sheet floors are not only tested on strength with concrete but also with floor mortar. The quality of this wet mortar has to be at least a quality C20-F4.
How much mortar do I need per m2?
Floor mortar on plate: C20-F4 quality, usage 22 kg/m2/cm.
Concrete on plate: C20/25 quality, usage 25 kg/m2/cm.
Attention!
Keep into account approximately 20 kg/m2 extra to fill the sheet cavities.
How long does the mortar have to dry?
After 2 to 3 days you can tread carefully on the floor.
After 1 week the floor has approximately 80% of its final strength.
Rule of thumb: 1 week per cm to reach the final strength.
Is there need for any additional reinforcement steel in the floor?
No, Duofor dovetailed sheets act as reinforcement due to its specific shape.
Is there need for any electrical grounding net in the floor?
No, you can connect your grounding wire directly to the Duofor dovetailed sheets.
How do I insure none leaking edges in a bathroom?
Horizontal and vertical edge connections become water tight by use of a standard seam sealing.
How do I make a dovetailed sheet floor with floor heating?
Apply the Duofor dovetailed sheets. If possible fasten the sheets lightly (maximum two over the sheet width) to the supporting construction. Keep the sheets separated from surrounding walls and piping with Duofor RS. Apply the heating tube right-angled to the profile onto the Duofor sheet using sufficient fixtures like DuoKlip. Use enough mortar to cover the heating tube with at least 20mm mortar.
Can I fix tiles directly onto the dovetailed sheet floor?
When a floor mortar is used it is possible to fix the tiles directly onto the dried floor. The floor must have dried for at least one week before applying the tiles. Preferably use a flexible tile adhesive.
Are Duofor dovetailed sheet floors 60 minutes fire resistant?
With Duofor dovetailed sheet floors with concrete a 60 minute fire resistant floor can be constructed. The supporting beams are the main factor to define the fire resistance of the construction. Contact Duofor for accurate advise on the fire resistance of your construction.
How do I make a noise insulating floor?
Apply Duofor DTS sound insulating strips between the dovetailed sheet floor and the supporting beams or floor boards. Use Duofor RS outer skirt strips to keep the edges of the floor from construction walls, piping and penetrations.
Attention!
Do not fasten the Duofor sheets to the supporting construction. Through these nails impact noise bridges will arise and contact noise transmission will occur.
Can I apply also another insulation material?
Use of other insulation material without consultation is strongly advised against. The specific low mass of the floor demands an optimum damping characteristic.
When the chosen material is too stiff it will be is disadvantageous for impact sound insulation.
When the chosen material is to soft there is great risk of settling. As a result the sound insulating capacities will decline and on top of that tears with walls, ceilings and piping will occur.
