The builder is still questioning the contract administrators final certificate 20 months after the final payment by the client. Can the builder still take this to arbitration.
The answer to this question lies in the prvisions of the Housing Grants, Construction and Regeneration Act 1996, and the amendments to it contained in the Local Democracy, Economic Development and Construction Act 2009 (this only applies assuming your contract was signed after October 2011).
Under these Acts, you have a statutory right to refer a dispute to adjudication. A ‘dispute’ is classed as any difference between the parties and there is no time limit under the Acts.
You therefore have until the Statute of Limitations takes effect to raise your dispute - 12 years from completion if the contract is signed as a deed, and 6 years if the contract is signed underhand.
You can find the Acts on the www.legislation.gov.uk website.
Arbitration is not constrained by these Acts - which relate solely to adjudication. Although similar sounding these are different forms of dispute resolution procedure.
Generally under JCT contracts, the parties have to opt into a specific arbitration in the contract, but it can still be used if both parties agree. Arbitration can be commenced at any time within the limitation period (6-12 years) for any claims which have not lapsed due to contract conditions.
The builder can take this dispute to arbitration if (1) it was agreed in the contract as a dispute resolution procedure or (2) he can get the employer to agree. Otherwise adjudication and litigation are open to him.