diff --git a/src/lbm/sweeps/SweepBase.h b/src/lbm/sweeps/SweepBase.h
index 1c7342a5120d56b5a2dac1cf646d4beac7639dd4..d3389cc60e612975851b885922f2dfd91279abb0 100644
--- a/src/lbm/sweeps/SweepBase.h
+++ b/src/lbm/sweeps/SweepBase.h
@@ -93,10 +93,10 @@ protected:
 
 
 
-   const BlockDataID src_;
+   const BlockDataID src_ {};
 
    const bool dstFromBlockData_;
-   const BlockDataID dst_;
+   const BlockDataID dst_ {};
    std::set< PdfField_T *, field::SwapableCompare< PdfField_T * > > dstFields_;
 
    Filter_T filter_;
diff --git a/src/pde/sweeps/SweepBase.h b/src/pde/sweeps/SweepBase.h
index a157d46dd1c95c38519c761837a7ffe0716f6055..031a3ee5917697b56697ca723d1bdb79406cc900 100644
--- a/src/pde/sweeps/SweepBase.h
+++ b/src/pde/sweeps/SweepBase.h
@@ -64,11 +64,11 @@ protected:
 
 
 
-   const BlockDataID src_; // "u"
-   const BlockDataID f_;
+   const BlockDataID src_ {}; // "u"
+   const BlockDataID f_ {};
 
    const bool dstFromBlockData_;
-   const BlockDataID dst_;
+   const BlockDataID dst_ {};
    std::set< Field_T *, field::SwapableCompare< Field_T * > > dstFields_;
 };
 
diff --git a/src/pe_coupling/discrete_particle_methods/evaluators/InteractionForceEvaluator.h b/src/pe_coupling/discrete_particle_methods/evaluators/InteractionForceEvaluator.h
index 17d3121898ec8e306502ffa55528c73fd9350282..11709d1e8f4c1dc0c182f64e51e5203db20d85e8 100644
--- a/src/pe_coupling/discrete_particle_methods/evaluators/InteractionForceEvaluator.h
+++ b/src/pe_coupling/discrete_particle_methods/evaluators/InteractionForceEvaluator.h
@@ -106,8 +106,8 @@ public:
 private:
 
    shared_ptr<StructuredBlockStorage> blockStorage_;
-   const BlockDataID bodyStorageID_;
-   const BlockDataID pdfFieldID_;
+   const BlockDataID bodyStorageID_ {};
+   const BlockDataID pdfFieldID_ {};
 
    std::function<Vector3<real_t> ( const Vector3<real_t> &, const Vector3<real_t> &, real_t, real_t, real_t, real_t )> dragForceCorrelationFunction_;
 
diff --git a/src/pe_coupling/discrete_particle_methods/evaluators/LubricationForceEvaluator.h b/src/pe_coupling/discrete_particle_methods/evaluators/LubricationForceEvaluator.h
index 63723eaa49018c758a7052455cce4e628db3afb8..b9bf10293b45ccbf7831871e2f1014cf783d3abd 100644
--- a/src/pe_coupling/discrete_particle_methods/evaluators/LubricationForceEvaluator.h
+++ b/src/pe_coupling/discrete_particle_methods/evaluators/LubricationForceEvaluator.h
@@ -78,8 +78,8 @@ private:
    // member variables
    shared_ptr<StructuredBlockStorage> blockStorage_;
    shared_ptr<pe::BodyStorage> globalBodyStorage_;
-   const BlockDataID pdfFieldID_;
-   const BlockDataID bodyStorageID_;
+   const BlockDataID pdfFieldID_ {};
+   const BlockDataID bodyStorageID_ {};
 
    real_t dynamicViscosity_;
    real_t cutOffDistance_;