There is no specific regulation but it would not be recommended behind a gas cook top. If there is a concern you could install the timber behind a glass splash back for protection. There is also a really nice tile that looks exactly like timber as another option.

I think that would look great with floorboards in a classic walnut colour, that would definitely look great with the light cabinets. If you want an idea of how it might look with the end finishes, you can type this into google and they should be able to show you a few.

When it comes to kitchen design for a ranch house renovation, you may want to consider the following factors: Space and layout: Ranch houses typically have an open floor plan, so you can create a kitchen that flows seamlessly with the surrounding living areas. Consider the space available and the placement of windows and doors when deciding on the layout of your kitchen. Style: Ranch houses often have a mid-century modern or rustic aesthetic, so incorporate these design elements into your kitchen renovation. For example, you could use warm wood tones, clean lines, and vintage-inspired fixtures to create a timeless and inviting space. Storage: Adequate storage is essential in any kitchen, but it's especially crucial in a ranch house where storage space may be limited. Consider incorporating cabinets, shelves, and other storage solutions that maximize the available space without overwhelming the room. Lighting: Good lighting is essential in any kitchen, but it's particularly important in a ranch house where natural light may be limited. Consider incorporating a mix of ambient, task, and accent lighting to create a warm and welcoming atmosphere. Ultimately, the best kitchen design option for your ranch house renovation will depend on your specific needs and preferences. Consider working with a professional designer or architect to help create a space that meets your functional and aesthetic goals. You can contact house tiling services Sydney. They are professionals in tiling

Maybe something like this. What colour terracotta are the existing tiles. Are they are strong orange or the more subtle deeper earthy terracotta?