Fosroc Nitobond AR
Single-component modified acrylic polymer emulsion — a bonding aid, gauging liquid and curing agent for cementitious repair and screed systems, supplied by Space Arc Engineering, an authorised Fosroc distributor and applicator.
What is it?
Fosroc Nitobond AR is a single-component, water-based modified acrylic polymer emulsion (polyacrylate latex). It works as a bonding aid, gauging liquid and curing agent for cementitious systems and is resistant to hydrolysis, making it suitable for external use.
Where is it used?
Used across India on concrete repair and rehabilitation works, plaster and masonry bonding, screed-to-substrate bonding, and as a curing membrane for Fosroc repair mortars such as Renderoc and Patchroc — in residential, commercial, industrial and infrastructure projects.
Why use it?
It improves the bond between new and old cementitious surfaces, raising slant-shear bond strength from approximately 5.0 to 20.0 N/mm2 when tested to BS 6319, while being low-VOC (13.5 g/litre) and acrylic-based for external durability.
How is it applied?
Applied by brush or roller as a bonding coat onto a prepared, sound substrate; used as a gauging liquid blended with cement-based mortars; or applied as a surface sealer (first coat diluted 1:1 with water, second coat as supplied). Coverage is approximately 6-8 m2/litre as a bonding aid.
About Fosroc Nitobond AR
Fosroc Nitobond AR is a single-component, modified acrylic polymer emulsion — a water-based polyacrylate latex — engineered to serve three roles in cementitious construction: a bonding aid, a gauging liquid and a curing agent. Because the acrylic polymer is resistant to hydrolysis, Nitobond AR is suitable for both internal and external applications, which distinguishes it within the Nitobond family for India’s exposed, monsoon-affected and high-humidity site conditions.
As a bonding aid, Nitobond AR is brush- or roller-applied to a clean, sound, prepared substrate to create a high-strength bond between freshly placed cementitious material and existing concrete, masonry or plaster. This is its most common use in concrete repair and rehabilitation, where reliable new-to-old adhesion is critical. As a gauging liquid, it is mixed into cement-based repair mortars and screeds to improve cohesion and durability. As a curing agent, it can be used to form a curing membrane over Fosroc repair mortars such as Renderoc and Patchroc.
It is important to position Nitobond AR correctly against its siblings and alternatives. Nitobond AR is acrylic — it is NOT an SBR (styrene-butadiene rubber) bonding agent; that is the separate Fosroc Nitobond SBR. It is also not an epoxy bonding agent (that role belongs to Fosroc Nitobond EP), nor is it a concrete admixture of the SNF or PCE superplasticiser type. Comparable acrylic and SBR bonding aids in the Indian market include products from BASF MasterEmaco / MasterBrace, Sika (such as SikaLatex / Sika Latex Power), and Pidilite Dr. Fixit Pidicrete ranges — but where a project specification or Fosroc repair system calls for Nitobond AR, the genuine product should be used to maintain warranty and system compatibility.
Space Arc Engineering supplies genuine Fosroc Nitobond AR as an authorised distributor and applicator, serving Delhi NCR and clients Pan-India. For exact dosage rates, mix designs and gauging ratios for your specific repair mortar or screed, always refer to the official Fosroc Technical Data Sheet (TDS) for Nitobond AR and to the TDS of the partnered repair product, or contact our technical team.
The technical insight
Nitobond AR’s defining technical property is hydrolysis resistance. Acrylic polymer emulsions, unlike some redispersible or SBR-based systems, do not break down readily in the presence of moisture and alkalinity over time — this is why Fosroc rates Nitobond AR as suitable for external use, an important distinction for India’s wet-dry cycling. The performance headline from the Fosroc TDS is the improvement in slant-shear bond strength to BS 6319: bonding with Nitobond AR raises the slant-shear bond strength from approximately 5.0 N/mm2 to approximately 20.0 N/mm2, demonstrating the value of a polymer bonding bridge between old and new cementitious layers. The product is low in volatile organic compounds (VOC content 13.5 g/litre per the Fosroc AU TDS), supporting use in occupied and enclosed spaces. Because dosage as a gauging liquid and as a waterproofing/admixture aid is mix-specific, these ratios must be taken directly from the current Fosroc TDS and not generalised — Space Arc deliberately does not publish a single fixed gauging ratio here, because the correct figure depends on the partnered cementitious system.
Where it is used
- Bonding aid between new and old concrete in structural repairs and rehabilitation
- Bonding cementitious render, plaster and screed to existing substrates
- Gauging liquid blended into cement-based repair mortars to improve cohesion and durability
- Curing membrane / curing agent over Fosroc repair mortars such as Renderoc and Patchroc
- Masonry and plaster bonding on internal and external surfaces
- Surface sealer on cementitious substrates (first coat diluted 1:1 with water, second coat as supplied)
Key advantages
- Single-component, water-based and easy to apply by brush or roller
- Acrylic polymer is resistant to hydrolysis, so it is suitable for external as well as internal use
- Significantly improves bond strength — slant-shear bond improves from approx. 5.0 to 20.0 N/mm2 to BS 6319
- Low VOC content (13.5 g/litre per Fosroc AU TDS), suitable for enclosed and occupied areas
- Multi-functional — acts as a bonding aid, gauging liquid and curing agent in one product
- Good coverage — approx. 6-8 m2/litre as a bonding aid, approx. 6-10 m2/litre as a surface sealer
- Available in convenient 1, 5 and 20 litre pack sizes for small repairs through to larger works
- Compatible with Fosroc cementitious repair systems such as Renderoc and Patchroc
Limitations & considerations
- Not a structural epoxy bonding agent — for high-load or chemically aggressive bonding, Fosroc Nitobond EP (epoxy) should be specified instead
- Not an SBR bonding aid — where an SBR-modified system is specified, use Fosroc Nitobond SBR rather than Nitobond AR
- Performance depends on correct substrate preparation — surfaces must be sound, clean and free of laitance, dust, oil and loose material
- Exact dosage as a gauging liquid and as an admixture must be taken from the current Fosroc TDS for the specific mix; no single universal ratio applies
- Like all polymer emulsions, application should follow Fosroc guidance on temperature, open time and overcoating windows
- Not a standalone waterproofing membrane — it is a bonding/gauging/curing aid within a cementitious system
Selection & best practice
Always start from a sound, clean, prepared substrate — remove all laitance, dust, oil, curing compounds and loose material, and dampen absorbent surfaces as directed by the Fosroc TDS. Apply Nitobond AR evenly by brush or roller as a bonding coat, and place the fresh cementitious material while the bonding coat is still tacky/wet within the open time stated by Fosroc. For gauging and admixture use, obtain the exact mix ratio from the current Fosroc Nitobond AR TDS and the TDS of the partnered repair mortar — do not rely on generic ratios. For surface sealer use, apply the first coat diluted 1:1 with water and the second coat as supplied. Confirm coverage, temperature limits and overcoating windows against the official datasheet, and store containers as specified. When in doubt, contact Space Arc Engineering’s technical team for project-specific guidance.
Specifications
| Chemical base | Single-component modified acrylic polymer emulsion (polyacrylate latex) |
| Specific gravity | approx. 1.025-1.04 g/cc (typical for acrylic emulsion) |
| VOC content | 13.5 g/litre (Fosroc AU TDS) |
| Coverage as bonding aid | approx. 6-8 m2/litre |
| Coverage as surface sealer | approx. 6-10 m2/litre; 1st coat diluted 1:1 with water, 2nd coat as supplied |
| Slant shear bond strength | improves approx. 5.0 to 20.0 N/mm2 when tested to BS 6319 |
| Reference standard | BS 6319 |
| Pack sizes | 1, 5 and 20 litre containers |
| Primary uses | Bonding aid (new-to-old concrete/masonry/plaster), gauging liquid for cementitious repair mortars, curing membrane (e.g. for Renderoc/Patchroc repairs) |
Industry use cases
Concrete repair & rehabilitation
Used as the bonding bridge between existing concrete and Fosroc repair mortars (e.g. Renderoc, Patchroc), improving slant-shear bond strength to BS 6319 on structural repair works across India.
Residential & commercial buildings
Bonds new plaster, render and screed to old masonry and concrete during renovation and remedial works, with hydrolysis resistance suiting external facades and wet areas.
Industrial flooring & screeds
Acts as a gauging liquid and bonding aid for cementitious screeds and toppings bonded to existing slabs, improving cohesion and durability of the repair layer.
Infrastructure & water-retaining structures
Applied where external durability matters — bridges, water tanks and exposed RCC — as a bonding and curing aid within Fosroc cementitious repair systems, per the project specification and TDS.
Frequently asked questions
Is Fosroc Nitobond AR an acrylic or SBR bonding agent?
Can Nitobond AR be used externally?
What is the coverage of Nitobond AR?
What pack sizes is Nitobond AR available in?
What dosage of Nitobond AR should I use as a gauging liquid?
How much does Nitobond AR improve bond strength?
Does Space Arc Engineering supply genuine Fosroc Nitobond AR?
How we position Fosroc Nitobond AR
Fosroc Nitobond AR is positioned as Fosroc’s acrylic (polyacrylate latex) bonding aid, gauging liquid and curing agent — the hydrolysis-resistant, externally-suitable choice within the Nitobond bonding range. It sits between Fosroc Nitobond SBR (the SBR-modified option) and Fosroc Nitobond EP (the high-strength epoxy option), and competes with acrylic/SBR bonding aids from BASF MasterEmaco, Sika (SikaLatex) and Pidilite Dr. Fixit Pidicrete. Space Arc Engineering supplies it as an authorised Fosroc distributor and applicator for Delhi NCR and Pan-India.
Related Concrete Repair products
Source Fosroc Nitobond AR for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.