After a bit of advice. Moved into 11 year old property and have noticed that the black sealant in the windows is either "leaking" down the window or there is a noticeable gap where the sealant has "shrunk". Windows are wooden framed double glazing. Any help gratefully appreciated and how to resolve these issues.
The glazing seal strip on the inside of the windows can be replaced easily, the problem will be finding the correct section - it must be a tight fit for security reasons.
The outside seal is part of the glazing beads and your chances of getting a replacement are very slim - see if fitting a larger section inner glazing seal strip will solve the problem.
The Black seal on the Timber windows between the Glass and the Bead or back rebate is probably Flexistrip. A Butyl rubber strip that is rather like putty on a roll. Unfortunatley some glass cleaning chemicals can make it soft and it then leaks out . Try buying some Butyl Glazing compound from your local glass shop and using a wide stripping type knife, scrape the Butyl into the gaps and smooth off.