How to repair silicone along shower base?

[DoSimpleBetter]

Hi folks, 

The silicone along the edge of my shower base has cracked in a few places (there's one main spot I'm worried about pictured below - in the centre of section 'A').

This is my first time working with any form of silicone/grout repair - and I'm trying to assess if this is a small job I can take on myself, or if I'd be better off engaging a professional for a larger job / more permanent fix. 

I'd love some advice on: 

• Is there such a thing as a patch repair for a problem like this, where I could remove a single line/edge of silicone and replace that, or does the repair need to be more of an 'everything all at once' type of job? (From my research I can see new silocine doesn't like sticking to old sillconine, which suggests it's best to avoid any kind of 'join' when doing the repair.)
• If it is possible to do just one section, which specific lines would you recommend I remove and replace (eg. Just A? A+B1+B2?)
• Are there any specific tips / resources you'd recommend for a job like this? 

[JacobZ]

Hi @DoSimpleBetter,

Thank you for your question about removing and replacing old silicone.

While you can remove and replace silicone in small sections, it will not be as effective long term as removing and replacing everything. This is because when silicone is still wet, it can be smoothed into one continuous bead with no gaps or obvious joins. When you are running new silicone into old silicone, there will be a very small weakness where the two sections join which can fail over time.

If you'd like to remove and replace sections, I'd suggest removing and replacing A and overlapping B1, B2, C2 and C3 by around 50-100mm. The new silicone will not stick amazingly well to the old, but it should be ok. Running a slightly wider bead than the old so the sides of the bead stick to the tile as well as the old silicone will also help.

Ultimately, if you want results that will last as long as possible, I'd suggest removing and replacing it all, but a repair job should be fine as long as the water is not pooling on it constantly and you keep an eye on it.

Check out How To Silicone a Gap for some guidance on the process. You can use painter's tape to get nice straight lines and silicone scrapers to strike off the bead of silicone. A good tip is to keep a bucket of water and plenty of rags handy as it's likely you'll need to do some clean up.

Let me know if you have any further questions.

Jacob